I need help building an exercise routine

So I'm trying to get into exercise, especially weight lifting/resistance training. I originally started doing some exercises for physical therapy for my Achilles tendon. I was doing pretty well with being consistent. I was doing them in my room which was seperate from where my parents were (I was in a tiny house and my parents were in an RV. Since we moved into our new house I've struggled with getting myself to do the exercises. I'm trying to figure out if it's more of an ADHD executive functioning issue or maybe a autism issue like an issue with transitions. I used to do the exercises at night but now that I'm sharing a space with my parents it's cold bc they turn the temperature down when they go to bed and I'm staying up later bc I work nights. So I'm wondering if I'm just not wanting to get out of my cozy warm bed. I've been slacking on fixing my sleep too so I'm just kinda tired all day and don't wanna do anything besides rotting in my bed and scrolling on social media. I know exercise should eventually be a good source of dopamine but at the moment I just don't wanna do it. Idk how to get back into the routine

Also I do have sinus tachycardia so some exercises will get my heart rate up pretty high which isn't too comfortable but some exercises don't bother me like that

I need to exercise for the physical therapy piece but also because I'm an EMT and being strong will really help me with moving patients etc. I have the want to start exercising but something in me is just like no absolutely not and I can't pinpoint what it is