Are cats just naturally non-listeners? Some people have told me that due to their "sassy" prideful or completely opposite (scared) attitudes, they are very tough to teach them to do really anything.
Dogs understand intention. When a human gives feedback, the dog understand that the human is conveying a message, and the dogs puts effort in understanding and learning from the experience. A dog also inherently wants to please its master because it knows that the master will take care of it when it is helpful.
A dog who listens to its master can be taught to not do something without ever having done it. If the master says no, then the dog knows to not to the thing it was about to do. Even if the dog doesn't understand it, it will defer to its master's judgment.
Cats don't understand intention. They are smart, but they simply do not register our voice as a message meant for them. Cats can learn, but only through practice.
A cat will only learn after learning the negative consequences of the action it took, and it will probably need repeated experiences before they learn. A cat will not defer to its master, it only acts on its own thoughts.
This is why cats are much harder (but not impossible) to train.
I tried the "force them to shake or sit, say the word, then give them treat" and my cats are quite loving so they didn't mind me pushing their backs a bit to allow them to sit, and they do somewhat come when I tap or clap.
While this is sometimes nothing more than a theoretical difference, a dog will come because it knows that you want it to come to you; but a cat will come because it wants to come to you.
That is a subtle but significant difference, and it dramatically impacts how you teach your pet.
I simply wish to teach them how to come when I say, and sit when I say sit.
Teaching your cat to come is quite simple. Call for them, and give them a treat. Do this even if the cat is already beside you, so you get the chance to prove to them that calling them means they get a treat. Next time, when your cat is not in the same room as you but it hears you calling, it will independently decide that it should go to you because you're probably going to be giving a treat.
Do this often enough, and the cat will learn that when it hears a particular sound (its name), that a treat is likely incoming.
My cats don't always come when I call them (I've never expected them to). But when I call all three of them (in the same order and tone of voice), they will always come, because I only do that as I'm putting food in their bowls.
One of these cats, however, is incessantly playful and always deeply interested in anything new. You cannot bring anything into the house without him inspecting it inside out. This cat always comes when I call him, I haven't even needed to train him for that. Because he respond to every impulse and he's just always up for some interaction.
Getting a cat to sit is a different thing though. Cats don't do something because they are told to. Going back to the example of calling them and giving them a treat, you are presenting them with an opportunity (a treat will be given) and it's up to them to decide whether they want that treat or not. This is exactly why my cats don't always come when I call them; sometimes they just don't want to get up out of a comfy spot (partly because another cat might take it).
Sitting on command is not an opportunity which the cat can choose to engage in. If the cat wanted to sit, it would already be sitting. The fact that it doesn't means that it doesn't want to sit.
It's not impossible, but it's not going to be easy to get a cat to understand that you want it to do something and expecting it to comply just because you are telling it to do so. That is something that dogs innately understand, but cats cannot comprehend.
The best way to approach a training it to put a cat in a situation where the intended behavior is beneficial. For example, a cat I used to have sat by the sliding glass door and meowed nonstop. I tried punishing him with a plant sprayer but he wouldn't stop.
What got him to stop is that I would used the plant sprayer from behind the couch, I did not have direct line of sight to the cat and needed to arc my shots over the couch. I used his meows to pinpoint his location. If he did not meow, I was not able to figure out where he was and I could not hit him. If he meowed, I could zero in on his position and had a good chance of hitting (or inconveniencing) him.
It took about 2-3 weeks for him to figure out that he would be safe if he didn't reveal his position. And that is exactly what I wanted him to do.
But I can't think of a way that you can use this tactic to get them to sit.