Answers for "how to push an existing repository from the command line"

git push existing repo

cd existing_folder
git init
git remote add origin https://gitlab.com/abc.git
git add .
git commit -m "Initial commit"
git push -u origin master

git push existing code to new repository

git remote add origin <remote repository URL>

push an existing repository from the command line

git remote add origin https://github.com/TaherSaid/my-pfe-informatique-mobile.git
git branch -M main
git push -u origin main

pushing an existing repository from cmd

git remote add origin <url>
git branch -M main
git push -u origin main