Description column width

Can anyone advise on below inquiries referring to attach screen shot?
(1) Can I adjust description column width which requiring wider space? I have read about themes but no ideal to do it
(2) Can I add the formula for total quantity ?
(3) Can I get the quantity in size ratio in inventory items list ?

Thanks a lot

Obviously, you are attempting to use a custom theme. The performance of these is your own responsibility. If you don’t have the necessary programming skills, hire a local programmer. Your problem is that you have added many custom fields, and each one takes some width. Eventually, you run out of room on the page.

No

Each inventory item needs to be separate. The same pant in size Small must be a different inventory item from size Medium.