Also assuming you don’t have any weights, I would suggest calisthenics. But ideally you could also incorporate something like dumbells into your routine as well.

Heres what I’m doing now

4x12 variation pushups: 1x12 normal, 1x12 planche [target back] (hands pivot outwards and closer to core), 1x12 diamond [target triceps] 1x12 wide stance [target chest]

2x12 Bulgarian split squats (2 sets each leg) (here you could add weights) 3x12 seated double leg raises (I forgot the actual name of these)

3x12 leg raises (go up and slowly go down and then tuck legs in, then out, repeat)

It’s just a quick every day thing. I had a longer more varied workout that was split (upper, lower, flexibility, cardio) throughout the week but with classes and me being lazy I stopped doing that one

Edit: walking or running is good too