Mmmk. Fail thread. Education time
Possible swaps: Anything. You can put whatever the hell you want into the car.
Common Swaps: Now these are what you're probably looking at. They have been done many times and covered in many different threads.
D-series- Mostly out of 90s civics, there's no real point in putting it in your integra. Don't do it.
B-series- Most common swap for our cars because they come out of our cars. They are all DOHC, some are vtec and some are not. Vtec heads tend to breathe better, not just go bawahhhh. Most commonly you'll see b16, b18, and b20. There is a b17 but at this point is rare and outdated.
The b16 is a 1.6 liter out of "special" civics, most commonly found in the 99-00 si, but some del sols come with them too. They're all vtec. It's a good strong engine but I still put it behind the b18.
The b18 is a 1.8 liter out of integras like ours. The common two are the b18a1, and the b18b1. They don't breathe well but they get pretty good fuel economy, unless the compression is through the roof or you're slamming boost into it don't expect it to be fast. The vtec versions are the more sought after. Most commonly in the us we see the b18c1 and sometimes the b18c5. The c5 is IMO the best AMERICAN b series you can buy. Jdm or ukdm engines are a little harder to come across but usually worth the money, vtec b18s all have a C then a number, sometimes it's just a C.
The b20 is just like a b18a1 or b1 just bored out to a 2.0 liter. It gives a little more torque but still has the same choking head on it. It comes out of the crv.
Ls/vtec and b20/vtec- now things are just getting crazy. These are Frankenstein engines. Most commonly an Ls or b20 block is fitted with a b16 or Gsr head. A few modifications along the way but these beasts rev high and pull hard for not much money. Tuning is a big factor in this.