How does an obese person workout??

Hey yall! I have decided this year is the year I actually change, and live a healthier life! As well as eating well, I have attempted to workout these past three days. I am attempting to start very small (only 15 minutes right now because that is all I can handle). I have a few small weights and just do some basic exercises (squats, short spurts of jogging, lifting light weights, ect). But I feel like I could be doing something more effectively. It’s hard to find workouts for people my size, though, so if you have any suggestions please let me know! I am a 300 ibs 18 year old, for reference.