Drug-store reading glasses only work if you have nothing but identical far-sightedness or near-sightedness in both eyes.
I am over 50 and have always had astigmatism, and deal with the lingering and ever-changing effects of a shingles scar on one cornea, so my glasses are anything by simple.
My computer glasses solution is to have one pair of trifocals for general use, and a pair of bifocals ground to give a general view of the computer screen, with a close-up along the bottom for looking at the gizmos I'm designing circuit boards for when I'm on the computer. It works pretty well, other than the inconvenience of having to change glasses a lot.