Here are the useful commands for SVN.
https://developer.wordpress.org/plugins/wordpress-org/how-to-use-subversion/
Checkout a SVN from WordPress, this will put it into the current directory. You can also add a destination folder after it.
svn co https://plugins.svn.wordpress.org/your-plugin-name
To commit
svn ci -m “Reason for commit” –username your_username –password your_password