git remote switching existing branch

Local branch a, b and no branch, branch later want to switch to the remote b

1. git remote update origin --prune update the list with the same remote local branch

2. git branch to view all local branches, whether to update the branch b

3. git checkout b switch to branch b

4. git merge a branch is merged onto a current branch b, the conflict resolve resolve conflicts

5. git push updates to the remote (if necessary)