You'll have to create an account on Garmin Connect to use your new 830. Somewhere in there is a setting that will make Garmin send Strava a copy of the data it records. Which will let you stop recording using Strava on your phone presumably.

You said you're hoping to see your progress, I don't know what that means specific to you and HR, I find some of the reports in Connect are useful. I don't use Strava personally and am happy with the Garmin as a training log.