First thing before you even start powerlifting is you want to be in a calorie surplus. A modest amount of 6000 should be just fine for you, we want to start off easy. Now after you've been bulking for 3 years, now you can start looking into supplements which you're going to want creatine, l glutamine, BCAAs, protein powder (casein and whey), casein custard, non stim pre workouts including nootropics, caffeine based pre workout, trenbolone acetate and clenbuterol. Those last 2 are the most important so I strongly suggest googling those first.
If you want a decent squat plug i'd suggest hitting up the local sex shop. I've been banned from most of mine but the only one that still allows me in (they're jealous of my gainz lol) is run by this really annoying 5ft 4 young fit tanned white asian latina slim thick girl that always eyes me off and licks her lips at me but I don't know why. Try and find a squat plug that will work best for your lifts, if you're starting out small and squatting light then you won't need anything big just yet. But the heavier you lift, the larger you want your plug to be as your sphincter will likely crush the small plugs to which I have demanded a refund for in the past. I'd strongly suggest buying an inflatable plug as you will only need to buy the one and can adjust it over time. Although the problem is they have the tendency to burst which reminds me of the time I was squatting a new max and I had just been rejected again (I hope i lose my virginity one day and i was so close to finally doing sex) so i was really upset and was trying to squat 680 and then my inflatable plug burst after i pumped it up to max, so there was a loud BANG from my ass and then i dropped the bar in my neck so it sandwiched me and then the whole gym looked at me and it was right as the cardio bunnies were walking past so everyone saw. So I did what anyone would in that situation and started screaming 'STOP LOOKING AT ME' at everyone walking past who were now backing away from me. So I ran out of the gym crying. My post workout shaker bottle of breast milk is still there. In the end it was a good workout and i'd still suggest the inflatable one though, the cute 5ft 6 slim thicc milf latina teen virgin white ebony attendant even gave me a refund on the plug and promised to show me how to properly use it and even tried to demo it on herself there and then when I took it back but I got scared and screamed at her 'NO WAY ♥♥♥' and ran out but I really think you should try powerlifting you should really do it
Powerlifting is the only way to reach Ricegum's physique