Cats that live outside are called feral cats and a colony is a group of feral cats living together.
Some things to do for a feral cat are feed them and take them to the vet. The best thing you can do is have them spayed or neutered because one female cat can have a lot of kittens. Then either adopt them or return them to living outside. It’s called trap, spay or neuter, and return. There are shelters and vet clinics that can lend out live traps for the cats that can’t easily be picked up and handled. And yes they can be adopted if given time, love, and patience.
You can find more information by asking someone at a local shelter or vet clinic. Or visit- Alley Cat Allies A website where you can find plans to build a cat house and more info on helping the feral cats in your neighborhood. Feral Cat Shelter Options