Yes, yes, yes! To use a computer monitor, you need the ability to accommodate or focus up close. Presbyopia is common and can be completely alleviated by use of glasses. Plus, lens tiniting can be used to reduce glare and improve contrast. See you ophthalmologist for a full evaluation and refraction.
Computer eye strain. Computer glasses are effective only if you have refractive error such as myopia, hyperopia or astigmatism. If you are prepresbyopic (generally under forty) and you have no latent hyperopia, myopia or astigmatism then "computer glasses" are not needed.
Yes. For people with presbyopia (difficulty with focusing closely), readers can work wonders. What they cannot address however are differences in focus between the eyes or astigmatism. For many people however, otc readers work great and are inexpensive. For the ultimate clarity, see your ophthalmologist and try some custom glasses.
Yes. They work best if you have no underlying refractive error or any cataract. Best to have someone check both eyes to see if you need custom bifocals or not.