I am having several issues with my conda installation on MacOS (latest). Conda used to work not long ago.

First.

conda env create --name newenv

EnvironmentFileNotFound: '/Users/user/Apps/environment.yml' file not found

Never seen this error, so I decided to update conda.

Second.
After

conda update -n base conda

I get:

==> WARNING: A newer version of conda exists. <==
  current version: 23.9.0
  latest version: 24.5.0

Please update conda by running

    $ conda update -n base -c defaults conda

Or to minimize the number of packages updated during conda update use

     conda install conda=24.5.0

None of the two suggested commands work: they do not perform the update. But this issue has been known for years and it is likely very hard to solve.

Third.
I decided not to uninstall/re-install conda and go on with the version I have.
So I ran:

conda env create --name newenv python=3.9

SpecNotFound: Invalid name 'python=3.9', try the format: user/package

I do not know what is wrong and do not know what to look for. I made some web searches but could not find anything.

Is there anyone with anything I can try before uninstalling conda?