check git remove by this command
git remote -v
Add second github remote
git remote add github https://github.com/organization/repo.git
check remote again
git remote -v
You can also remove old remote
git remote remove origin
(change origin name according to you old remote-name)
From Now You should git pull/push with name of remotes:
git pull <remote-name> <branchname>
git pull github stag
Changes Upstrem Branch for New Remote
git branch --set-upstream-to=github/master main