You can switch between levels if there are exercises in the next level that you think you can do safely. Wear sensible footwear, keep some water to hand and keep a sturdy chair next to you for stability if you are not used to exercising.
Seated back extension
Seated leg lift
Seated rotations
Sit to stand using hands
Wall push
Supported half squats
Seated leg lift with hold
Leg marching
Seated reach up and pull down
Kneeling push up
Scapula push ups
Bodyweight hip hinge
Seated cycling
Bodyweight squats
Full push up