I want to use the following water level sensor to indicate whether water is filled till the top in a tank

Anti-Corrosion Water Level Sensor with Ball Float Switch

I am planning to connect one terminal to this to 3.3v of pi and other one to the GPIO of the Pi. The GPIO would be configured as a input. It would be queried again and again to know whether the tank has filled or not.
Once the water gets filled it would close and the GPIO pin would get the input as HIGH i.e 3.3v. There are two things that I need to think about

1. Can GPIO handle the voltage – answer to this in my opinion is YES as that is the safe level for GPIO. Maybe I am wrong here.
2. Can GPIO handle the current – I DON’T know the answer to this question.

Also connecting 3.3v to GPIO pin would that be safe ?
Would it work always without damaging my Pi ?
Do I need to use another circuit for limiting current to it ?
If yes how should I go about this and are there some online resource to learn about this?