you're describing several different issues,,, negative side bsmt 'waterproofer' mtls (drylock, thoroseal, etc) are usually cementitious-bas'd liquids sold in apron stores,,, they're worthless impo in that you're not able to prevent wtr from infiltrating the blocks nor can you successfully inject 'em w/any mtl that'd resolve the problem w/i it just finding another spot for ingress,,, you can 'manage' the wtr but its hard, back-breaking work best left to pro's who have insurance,,, you would also have a responsible party to sue whereas, if you do it yourself, guess who'd be responsible ? ? ?
fountains & pools aren't hollow therefore they can be successfully injected w/either hydrophyllic/hydrophobic mtls depending if you're trying to prevent wtr loss OR intrusion.
garage floors can be repair'd by 'chasing' crks w/diamond blade & grinder then installing a flexible epoxy designed for that application.