Rclone being a command line program can't monitor your file system for changes and automatically synchronize.
However, if you combine Rclone with Freefilesync software you can achieve what you want. It provides real-time synchronization in the background for the operating system so if you have your Cloud Drive mounted to the drive letter or a folder in Linux you can use freefilesync real time synchronization feature to keep your local folder and your remote folder synchronized.
You can optionally as I do set up encryption so all of your files on your OneDrive are unreadable by Microsoft.
One note here. Bisync is not as straightforward as rclone sync (but not rocket science neither). I suggest you read all documentation first and experiment with some test data until you get it working.
Full description (including step by step getting started) is here in case you miss this link: