So I've been confused by the locked door here for ages, and noted that you can just break a window and climb in
Then just so happened to save the game inside the building and finished playing for the day and close the game, when I reloaded I loaded in just outside the ranch and ran back in to find the door is unlocked!
Cue spending an hour an a half going through Chapter 1 in a new save to demonstrate the whole thing for a tiktok but managed it and the video can be found here;