$ git remote set-url --add origin {url}
				

It adds a new url to the remote origin, when pushes it will syncronize to all urls defined.
Ex.:

  $ git push -u origin main
  Enumerating objects: 5, done.
  Counting objects: 100% (5/5), done.
  Delta compression using up to 8 threads
  Compressing objects: 100% (3/3), done.
  Writing objects: 100% (3/3), 561 bytes | 561.00 KiB/s, done.
  Total 3 (delta 2), reused 0 (delta 0), pack-reused 0 (from 0)
  To gitlab.com:kocyeb/kocyeb.cc.git
	 fe14e97..771481e  main -> main
  branch 'main' set up to track 'origin/main'.
  Enumerating objects: 5, done.
  Counting objects: 100% (5/5), done.
  Delta compression using up to 8 threads
  Compressing objects: 100% (3/3), done.
  Writing objects: 100% (3/3), 561 bytes | 561.00 KiB/s, done.
  Total 3 (delta 2), reused 0 (delta 0), pack-reused 0 (from 0)
  To github.com:kocyeb/kocyeb.cc.git
	 fe14e97..771481e  main -> main
  branch 'main' set up to track 'origin/main'.

				

Added URLs can be seen with this command:

  $ git remote get-url --all origin
  git@gitlab.com:kocyeb/kocyeb.cc.git
  git@github.com:kocyeb/kocyeb.cc.git
			

https://git-scm.com/docs/git-remote#Documentation/git-remote.txt-set-url