Do animals feel love and emotion?

Yes. Animals absolutely have emotions. In fact, many animals, like cats, are extremely emotional creatures, on account of not having as highly developed parts of the brain that deal with emotional regulation. Affection? Absolutely. Love? Yes, but not generally in the same ways as people.

Do cats and dogs actually feel affection when you treat them right or is it really just an instinct for “more food and drink” etc?

I have a little cat that adores me. He likes come right up to my face and head-butt me forcefully (a behavior called bunting) and he likes to fall asleep gazing at me. Domestic cats and dogs are social creatures. Left to their own devices, they will engage in social behaviors unrelated to survival and biology.

I don’t think I’ve ever seen dogs, cats and other domestic animals smile because they’re happy and show love to their owners for treating them right.

Oh they absolutely do smile, just differently than humans. Cats are especially subtle abd communicative in their body language. It’s also with noting that what humans think of as smiling, to most animals is an aggression display.

Yeah I see memes but those are either photoshopped or snapped at the perfect moment to make it look like they’re smiling.

Domestic dogs and cats communicate a lot with body language, the majority of it being pure emotion. Their body language, however, is different from our own. You have to meet them halfway in communication; learning to listen to what they are saying.