You should try to match the waterproofing the to method of tanning the leather. They are not all the same. Contact the manufacturer and they will tell you what they recommend.
If you can’t do that, there are several general purpose sealants out there. Sno Seal used to be the go to brand, but there are better products on the market these days that are more breathable and won’t make your feet sweat as much. I wouldn’t use Sno Seal on gloves.
My preferred method is to use Lexol cleaner first, then Lexol conditioner, then finish up with two coats of Obenauf’s leather preservative. The Obenauf’s has beeswax in it. It’s time consuming but the results are great.
Treating leather with this type of stuff is not magic. There are trade-offs involved - breathability goes down is the main one. Also, as far as I’m aware, the treatments are not permanent - you do need to keep re-applying.