Not a school teacher but due to Covid, I had to purchase 3 computers for my kids to do virtual school. Can I deduct this items?

No.   Sorry.

EDUCATION EXPENSES

Education expenses for grades K-12 are not deductible on your Federal return, whether for private, public, or home schooling, nor are the expenses for tutoring, after school lessons or after school activities, such as dance lessons, sports, etc.  Some states allow deductions/credits for K-12 education and/or home schooling expenses; if your state has these deductions available, you will be prompted to enter them when you prepare your state return.  (As far as I know, the states that offer any sort of K-12 deductions/credits are Arizona,  Illinois, Indiana, Iowa,Louisiana, Minnesota, and Wisconsin)

No, unfortunately, this expense is not considered qualified education expense and is not deductible.

It would be deductible if it is a necessary requirement for enrollment or attendance at an educational institution (college or university),