You don’t water succulents and cacti, they’re desert plants. They want to be somewhere sunny and dry. You give them a small spritz of water rather than pouring water straight on. If the soil is wet, they rot. If the soil is too wet, you can unpot them, wrap the soil in kitchen paper overnight and then leave them unwatered for a few months. I rescued one my dad overwatered that was starting to smell bad, and it’s fine now.