Weight loss help

Hi girls - I’m incredibly unhappy with my weight at the moment and I’m wanting to lose a few kilos.. due to heart problems I’m not able to go to the gym or play sport until the doctors can get my health managed (this is what the doctor said) I was very active but not being able to do much I have put on the weight (I’m 17 and roughly 83kgs) I was wondering if anyone has some tips or routines that’s is low intensity that I could get in the routine of doing? Also I lack motivation - does anyone have any tips to stay motivated?

I appreciate any feedback or comments💖