Hey @Vadym Dytyniak I'll do my best to answer these
1. Restarting a flow run re-triggers the whole run but you are correct that is only actually re-runs tasks in a failed, canceled or crashed state, generally speaking if you wanted a fresh run I'd probably suggest just kicking off a new flow run, is there a reason in this case you wouldn't want to do that?
2. To my knowledge we don't have specific support for cancelling a flow run as of now but it is definitely on the roadmap to include.