I started mine[1] in earnest in the last few months; it's a mixture of programming and let's plays. I'd say don't overthink it; just start recording and uploading. You'll always find things to improve in subsequent videos and it's a really important part of finding your own voice on video platforms.
Try to make a recording and uploading schedule, don't make too many videos public at once and use the schedule function to spread out when your new videos appear in subscribers' feeds, because people are quick to unsubscribe if they think they see "too much of you" in their subscriptions feed.