Two weeks ago, I started working out at home. I follow a Youtube channel that focuses on fitness. Every night the creator goes life on Youtube, and she works out at fome for 30 minutes. (to reference the "she" in your sentence, you need to clarify who she is) Many people who are subscribed to her channel, like me, exercise watching her videos. I thought it wouldn't be motivating because I used to go to a gym for five years, and exercising at home wasn't helpful in the past, but after a couple of days of exercising with her, I found that it made me feel good and energetic. She also sells some exercising equipment; I bought a spine corrector from her and have been working out watching her Youtube videos. (because you are referencing specific exercising videos, and not her channel as a whole) I het backache quite easily and need to be very careful when I work out. Spine corrector workouts are really good to correct my spine’s curves and strengthen my abdominals. It’s also lowered my stress level so much. (don't say first of all since you have already listed other reasons) I’ll try to work out at least three times a week to get into shape. (this sentence makes sense, but you need to change the tense if you want it to fit into your paragraph). Let me know if you've any questions :)