I just join this forum and don’t know how to use or how it works.
Best place to start is read the documentation: https://docs.gitlab.com/
Install it, configure it, google how to use git, etc since git commands are what you will use to download your repositories and work on them for pushing commits etc.
Then when you actually have exact questions to ask with problems you are experiencing, you can then post on the forum and ask for assistance. Until then you have a quite a bit of reading and learning to do. Just like we all had to do when we decided to install and use Gitlab, etc.
Thankyou for your response.