It really depends on what you're after, and what kind of budget you have.

The first thing to establish is if you want to have maximum performance and you don't care about noise, heat, energy consumption, etc. If that's the case, then just grab a few Bitmain Antminer S19 Pro+ Hyd which will give you 198Th each at 5445W and 50db. There are other good ones as well if you can't find that one, here's a good list: https://www.asicminervalue.com

On the other hand, if you want to mine at home with a quiet machine, then grab one or more Apollo BTCs and/or Compac Fs. Those are currently the best silent miners for home. Each Apollo can generate between 2-3TH/s+ depending on the amount of heat/noise/power you want. Each Compac F can run at about 300GH/s and are basically as quiet as you can manage to get a fan to run as they come without a fan although they need one.

That's the hardware part done, now for the pool, there are a few out there, but the simplest one to run is ckpool solo as you just need to point the miner to the pool, no need to register or anything: https://solo.ckpool.org