Search this site for other threads on eyeglasses--probably in the Reenactors Forum. Here are three from the bottom of this page (didn't even have to search):
https://civilwartalk.com/threads/eyeglasses-spectacles-a-question-for-reenactors.129273/
https://civilwartalk.com/threads/eyeglasses-worn-by-soldiers.109746/
https://civilwartalk.com/threads/eyeglasses.82739/
Eyeglasses of the Civil War period did not have those nose-gripping pieces that your glasses have--those are 20th+ century. Don't try to cut them off--I tried that once with an old pair of reading glasses and was left with very sharp edges (ouch!) and a broken frame. Period eyewear also has smaller frames.
I no longer (since my cataract surgery with lens implants) need glasses for distance vision (although I do need them to drive), but I do need reading/sewing glasses for close-up work. (We ladies do a lot of sewing and other close work at reenactments.) I was able to find, some years ago, some halfway decent reading glasses with period frames. Not the best, but at least more period than your modern eyewear.
If you absolutely cannot wear contact lenses (most people's solution), you can buy reproduction 19th century frames and have your prescription put in. You may have to search for an oculist who will do this, but many will. Unless your vision changes radically (in which case you may need medical intervention anyway), you should be able to get along with them for the next ten years.
If you can possibly manage to see well enough to march with your group without running into a tree, try to get along on the field without them, which is what most nearsighted Civil War soldiers did (see second reference above). After all, nobody back then had to pass a drivers license vision exam! Unless you plan to spend evenings reading outside your tent instead of socializing around the camp fire, you probably won't need closeup vision.