git add upstream https://github.com/harshraj22/Practice_plan.git
(add upstream branch, as you created local git repo now, it isn't expected to have an upstream)
git fetch upstream
(fetch all changes from upstream to local repo)
git rebase upstream/master
(rebase your current branch from master of upstream, you can also use git merge --allow-unrelated-histories upstream/master if you prefer merge commit)
git remote rm origin
(remove reference to origin, if exists, can be verified using git remote -vv)
git remote add origin https://github.com/harshraj22/Practice_plan.git
(add remote repo as origin, this is where we will push our commits)
git push origin master
(if everything works well, push your second one here)