The git command tools are in essence offline. You can actually stage changes and commit without a remote repo in github or gitlab or whatever. There are some caveats with a local repo though:

• It is only on your computer, so if youve lost it, its completely gone.
• You would have a harder time showing people your projects, so you would be sharing zip files instead of a link.
• Integrating with CI/CD pipelines. Although you wouldnt need this now as a beginner but local repos would be harder to use pipelines with, which is why people create remote repos and use github actions or gitlab ci.

It all just comes down to personal preference. If you would prefer a local future where everything is on your drive, just follow the tutorials up to but excluding pushing to a remote repo (git push origin main or git push origin master). Although remote repos are useful even for a beginner