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How to Work With Forks on Remote Repositories With Git
Step 1: Once you forked a remote repository, add the original repository as a new remote called “upstream”
git remote add upstream <ORIGINAL_REPOSITORY_URL>
Step 2: Fetch the branches of the upstream remote
git fetch upstream
Step 3: Update your branch with the upstream
git rebase upstream/<BRANCH>
Step 4: Force push the updated branch to your fork’s remote repository
git push origin <BRANCH> --force
Step 5: Start working on the updated fork using a new feature branch
git switch -c <FEATURE_BRANCH>
Step 6: Work as usual, write great code and add your commits
Step 7: Before pushing your changes to create a merge request, fetch and rebase again to upstream
git fetch upstream
git rebase upstream/<BRANCH>
Step 8: Push the feature branch
git push -u origin HEAD
Step 9: Create the merge request using the url given in the push status message (example for gitlab, actual behaviour may differ depending on used git server software)
https://<HOST>/<USER>/<REPO>/-/merge_requests/new?merge_request%5Bsource_branch%5D=<FEATURE_BRANCH>