get 30 level enchants
Enchantments

prot 4 is the best most likely to get also. Feather falling, swift sneak, and respiration don’t hurt,
but absolutely don’t get thorns. Your armor will break so fast

I personally just make an xp farm(gold farm is the best, I recommend ianxo4's easy and super cheap design).
Then I get a few stacks of lapis and some books and just enchant at level 30 everything so that I have at least prot 4 unbreaking 3 on everything, and I keep enchanting the helmet until I get aqua affinity AND respiration 3, as well as Feather Falling 4 and depth strider 3 on the boots. Grindstone as much as you need because xp isnt an issue with the gold farm. Get mending from villagers, swift sneak from ancient cities, and soul speed from piglin bartering or bastions.
I just got full dim armor what is the best strat for enchanting it