If you try to push some changes to your private GitHub repositories, Git will ask you for credential, but, even if you provide the correct ones, it will fail.
It is possible to easily bypass this problem. Run:
sudo apt install gh
Where gh
is GitHub CLI. It is necessary to authenticate.
Then, run:
gh auth login
Next, follow the instruction on the screen. When requested, I think it is better to choose HTTPS as authentication method.
Now, you can push whatever you want to your private GitHub repositories using regular Git commands.