There are so many variables to consider (depending on how deep into the rabbit hole you care go go) that you sort of have to pick a place to start and work on your "sampler sets" from there. The easiest ones to lock down are roast darkness and grind size. This is what I did recently-ish (after lockdown was over, but while we were all doing fun lockdown hobby-projects):

• Find a fancy supermarket with its own coffee grinder and whole bean selection near you -- by me both Whole Foods and Fresh Market have them, as does the specialty Italian market.
• Ask what the minimum amount of coffee is that they're willing to sell (in places that grind for you sometimes there is like a 1/8 lb minimum). Go with enough beans to brew yourself and your wife a cup or two each. 1/8 lb (2oz) is actually a good amount.
• Try 3 or 4 varieties at once. I'd say start with roasting depth first. The market will usually have at least a light, a medium a dark and a French or extra dark roast option. Buy a small amount of each one using the same grind setting for each.
• Try them all in a small period of time, always brewing them the same way. I'm not saying go home and drink 4 cups of coffee back to back (though I'm also not saying that), but do it in a day or two. When you're buying 12oz bags from the store it might take a few days to get through, which could make it a long time before you find what you like.

If your market is like mine they have a "house bean" that they sell at each of these darknesses, but even if that's not the case roasting has such a significant effect on coffee flavor it's still a good variable to knock out first.

Once you have that dialed in, you can go back to the store and get 3-4 samples of your favorite pick now at different grind sizes, or (if you're lucky) find 3-4 different bean options in your preferred darkness. The key is being able to buy in small quantities so you can try a bunch of options while keeping costs under control and not drinking weeks worth of coffees that you don't really like.