The uppers look great, but that’s a “heat welt”, which is a fancy way of saying the top is attached to the sole by hot rubber/plastic. Mind you, it’s neatly done and textured on top to look like stitching but it’s not a Goodyear welt. Trying to get them resoled would be a pain in the backside, the old sole would have to be ground down to form a sort of welt/midsole to which a new sole would be attached by cement or glue. It’s possible, we do it in my shop, but it’s not nearly as good as a Goodyear welt.
You’re running the risk that these will last only as long as the original soles, which is a shame, because the uppers are going to outlast those bottoms by a considerable margin. You’ll get 2-5 years (depending on how much walking you do and on what) out of those soles, which look at least somewhat durable (hard to say since it’s a picture and now something I can actually handle) before you have either attempt a resole (which may not work) or pitch them.
If you do want to try to get them resole please do not wait too long one that - there needs to be enough of the old sole left to form that midsole I was talking about. Wear them down too far and that’s it, they’re done. Also, if the synthetic they used to make the “welt” is the wrong sort it will simply self-destruct over time, in which case there is nothing to be done.
If you want a 20 year pair of boots look for a Goodyear welt.