As you can see I created a home page with a button in first column to create new customer ID and insert some data.
In my code I made 3 tables in the same database to divide informations and than show up in a simpler way datas.

My idea is: in the home page you can see all customers informations from dataDBG_clienti (In a second time I would add a search box), thant you can double click on one customer and open a new window to add tansactions and store them in dataDBG_credit or dataDBG_debit in base of the kind of transaction is.

import tkinter as tk 
import tkinter
from tkinter import ttk
from tkinter import *
import tkinter.messagebox
import sqlite3
import sys

home = tk.Tk()
home.title("DBG - Cassaforte")
home.geometry("1280x720")
home_frame = tk.Frame(home)



columns = []
for i in range(2):
    frame = tk.Frame(home, borderwidth=1, relief="raised", background="white")
    columns.append(frame)

home.grid_rowconfigure(0, weight=1)
for column, f in enumerate(columns):
    f.grid(row=0, column=column, sticky="nsew")
    home.grid_columnconfigure(column, weight=1, uniform="column")

def open_newcustomerwindow():

    def enter_data():

        #informazioni cliente
        name = name_entry.get()
        surname = surname_entry.get()
        id = name+surname


        if name and surname:
            phone = phone_entry.get()
            email = email_entry.get()

            #informazioni credito
            creditamount = credit_amount_entry.get()
            creditmetod = credit_metod_combobox.get()

            #informazioni debito
            debitamount = debit_amount_entry.get()
            debitratenumber = debit_ratenumber_combobox.get()

            #connessione e creazione del database

            conn = sqlite3.connect('dataDBG.db')
            table_create_query = '''CREATE TABLE IF NOT EXISTS dataDBG_clienti
                (id TEXT, name TEXT, surname TEXT, phone INT, email TEXT)
                '''
            conn.execute(table_create_query)

            table_create_query = '''CREATE TABLE IF NOT EXISTS dataDBG_credit
                (id TEXT, creditamount NUMBER, creditmetod TEXT)
                '''
            conn.execute(table_create_query)

            table_create_query = '''CREATE TABLE IF NOT EXISTS dataDBG_debit
                (id TEXT, debitamount NUMBER, debitratenumber INT)
                '''
            conn.execute(table_create_query)
            

            #inserimento dati
            data_insert_query = '''INSERT INTO dataDBG_clienti
                (id, name, surname, phone, email) VALUES (?, ?, ?, ?, ?)'''
            data_insert_tuple = (id, name, surname, phone, email)
            cursor = conn.cursor()
            cursor.execute(data_insert_query, data_insert_tuple)
            conn.commit()
           

            data_insert_query = '''INSERT INTO dataDBG_credit
                (id, creditamount, creditmetod) VALUES (?, ?, ?)'''
            data_insert_tuple = (id, creditamount, creditmetod)
            cursor = conn.cursor()
            cursor.execute(data_insert_query, data_insert_tuple)
            conn.commit()
           
            
            data_insert_query = '''INSERT INTO dataDBG_debit
                (id, debitamount, debitratenumber) VALUES (?, ?, ?)'''
            data_insert_tuple = (id, debitamount, debitratenumber)
            cursor = conn.cursor()
            cursor.execute(data_insert_query, data_insert_tuple)
            conn.commit()
            conn.close()
            tkinter.messagebox.showinfo(title="Completato", message="Informazioni salvate correttamente")
            form_newcustomer.destroy()

         
        else:
            tkinter.messagebox.showwarning(title="Errore", message="Nome e/o Cognome non possono essere lasciati vuoti")

    form_newcustomer = tk.Toplevel(home)
    form_newcustomer.title("Nuovo Cliente")
    form_newcustomer_label = tk.Label(form_newcustomer, text="Inserire le informazioni sul nuovo Cliente")

    frame = tkinter.Frame(form_newcustomer)
    frame.pack()

    #informazioni cliente
    user_info_frame = tkinter.LabelFrame(frame, text="Informazioni Cliente")
    user_info_frame.grid(row= 0, column=0, padx=20, pady=20)

    #etichette campi Cliente
    name_label = tkinter.Label(user_info_frame, text="Nome")
    name_label.grid(row=0, column=0)
    surname_label = tkinter.Label(user_info_frame, text="Cognome")
    surname_label.grid(row=0, column=1)
    phone_label = tkinter.Label(user_info_frame, text="Telefono")
    phone_label.grid(row=2, column=0)
    email_label = tkinter.Label(user_info_frame, text="E-Mail")
    email_label.grid(row=2, column=1)

    #campi inserimento dati Cliente
    name_entry = tkinter.Entry(user_info_frame)
    surname_entry = tkinter.Entry(user_info_frame)
    phone_entry = tkinter.Entry(user_info_frame)
    email_entry = tkinter.Entry(user_info_frame)
   
    name_entry.grid(row=1, column=0)
    surname_entry.grid(row=1, column=1)
    phone_entry.grid(row=3, column=0)
    email_entry.grid(row=3, column=1)

    #informazioni credito
    credit_frame = tkinter.LabelFrame(frame, text="Credito")
    credit_frame.grid(row= 1, column=0, padx=20, pady=20)

    #etichette campi Credito
    credit_label = tkinter.Label(credit_frame, text="Importo")
    credit_label.grid(row=0, column=0)
    credit_metod_label = tkinter.Label(credit_frame, text="Metodo di pagamento")
    credit_metod_label.grid(row=0, column=1)

    #campi inserimento Credito
    credit_amount_entry = tkinter.Entry(credit_frame)
    credit_metod_combobox = ttk.Combobox(credit_frame, values=["Contanti","Carta","Bonifico","Permuta"])

    credit_amount_entry.grid(row=1, column=0)
    credit_metod_combobox.grid(row=1, column=1)

    #informazioni Debito
    debit_frame = tkinter.LabelFrame(frame, text="Rateizzazione")
    debit_frame.grid(row= 2, column=0, padx=20, pady=20)

    #etichette campi Debito
    debit_amount_label = tkinter.Label(debit_frame, text="Importo totale")
    debit_amount_label.grid(row=0, column=0)

    debit_ratenumber_label = tkinter.Label(debit_frame, text="Numero rate")
    debit_ratenumber_label.grid(row=0, column=1)

    #campi inserimento Debito
    debit_amount_entry = tkinter.Entry(debit_frame)
    debit_ratenumber_combobox = ttk.Combobox(debit_frame, values=["0","1","2","3","4","5","6","7","8","9","10","11","12"])


    debit_amount_entry.grid(row=1, column=0)
    debit_ratenumber_combobox.grid(row=1, column=1)

    #pulsante funzione salvataggio 
    button_frame = tkinter.LabelFrame(frame, text="")
    button_frame.grid(row= 3, column=0, padx=20, pady=20)
    save_button = tkinter.Button(button_frame, text="Salva", command=enter_data)
    save_button.grid(row=0, column=2)



    #allineamento widget

    for widget in user_info_frame.winfo_children():
        widget.grid_configure(padx=10, pady=5)

    form_newcustomer.mainloop()

Button(home, text="Aggiungi nuovo cliente",command=open_newcustomerwindow).grid(row=0, column=0)



home.mainloop()

Now I would fill the second column with a database database’s table.
How can I do that?