Does anybody know what to do with this?

Hello there i have 2 questions for the using the computer

im having this problem while using the PC for a long time

a few years ago i used to have this computer desk for the computer and used it pretty good untill ive brought a new high chair which was pretty much a pain to look down at the computer and ive couldnt raise up the monitor because it had a shelf above it

ive brought a new desk place and using it for some reason give me a problem with my nerves in my arms,i have some chores like dishwashing etc anyway after using it causes my hands to feel somewhat  pretty numb and its hard for me to hold stuff up

another problem with using the computer i like putting books under the monitor so i dont have to bend down my neck,i have been suffering after using the monitor when placed on a desk regulary after one hour i feel much less comfterable sitting on my tailbone in a weird position and bending my neck down and some breathing problems com with that

the problem that comes with raising the bottom-middle screen at eye level that is that it causes my whole upper body to lean towards the hand that im using [which means] lets say im using only the right hand on mouse to surfe on the internet or on fps games its pretty weird to say but my head and upper troso leans to the right after that [much feels like it]

pretty much sounds weird if i put it that way but ive been experiencing this for much for a year and stopped playing or using the computer much because of this.