Yes, I know this is the ultimate noob question. But when a combo says like, “cancel the H.kick into forward-L.punch” do they mean just press it before the animation for the H.kick ends? or is there something specific you must do, like press a different button before the L.punch? I know this is a very nooby question, but please help : )
try doing crouch Medium Kick into Hadouken, using ryu.
hold down, press kick. Just as you press kick, slide your finger to the left or right (on the dpad, whichever way faces your opponent) and then hit a punch button. it should do a low kick and then a hadoken right after, you won’t see ryu stretch out his leg and then pull back, the animation is interrupted by the animation of a hadouken.
yes canceling is inputting the next move before the animation ends. while linking is pressing after the animation ends but before the opponent has come out of hit stun.
The easiest moves to cancel are shoto’s, like crouch medium kick, hadouken. They can be trickier when trying to link normals, such as Guiles light kick, light punch, medium punch, flash kick combo. Practice with Ryu/ken etc first.
Yup practicing with shotos is always the easiest way to learn 
Good luck.
Keep in mind that the input for the move you want to cancel to has to be done during the animation of the first move. So, think fast, then slow it down, then speed it up again.
Wax on, wax off.