So I mostly hav to sit on a desk for 13 hours a day even on weekends( I'm 18 year old student who is a bit over weight too) because of which I have severe back problems. I want to change this and want to decrease my weight.

Here for back pain someone recommended me that if I do exercises like jogging or skipping rope my back ache might increase and get worse, but I actually jump rope regularly.

What exercises can I do to decrease weight which don't put any extra pressure on my back or cause it any harm ??

So I mostly have to sit at a desk for 13 hours a day, even on weekends  (I'm an 18 year old student who is a bit over weight too) because of which I have severe back problems. I want to change this and want to decrease my weight.

Here for back pain someone recommended me that if I do exercises like jogging or skipping rope my back ache might increase and get worse, but I actually jump rope regularly.

What exercises can I do to decrease weight which don't put any extra pressure on my back or cause it any harm?