What does 'sort of' mean?

Shouldn't I put "the" between "play" and "guitar"? Like, "play the guitar."

No, it is not necessary to put "the" between those two words. Using "the" is considered an article in English that describes the noun. It functions as both an adjective and an adverb. However, one does not need to put "the" before the noun because the noun can stand on its own. Rapunzel will still be understood if she used "the" between those two words or not.

What is the difference between "important to" and "important for"?

Great question. The simple answer is that "important to" is something you value, while "important for" is something you need or, that will help you in some way. It can be a little bit vague if you're talking about personal experiences. For example, passing your exam is something you put a high value on and will also benefit you in terms of a career, so in this case, it would be "important to" and "important for" you. Ex: It's important for you to get well. Ex: It's important to your family that you get well. Ex: My son's education is very important for his future. Ex: My son's education is very important to me.

What is "without further ado"?

"Without further ado" is an idiom that means "without waiting any longer". This idiom is often used when introducing someone or something to an audience. Ex: Without further ado, I present to you the group you've all been waiting for - BTS!

Can I use "catch" instead of "fetch"?

The word "fetch" means for and then bring back, it is used in this video because the stick is first thrown and then the boy expects the dog to go and get it. This is actually a game played with dogs and the game is called "fetch". If we used the word "catch" in this context, it would mean the act of grabbing an object in motion, in this case, the stick. Ex: Can you fetch me that bag? Ex: A. Catch! B. No! Don't throw it.

Why do you always put the first person(=the speaker) at the end whenever you list multiple people in order?

From what I understand, the main reason is that it's polite! But it's used so much that it's considered grammatically and formally correct. Ex: My mother and I went to the shops to get ingredients for dinner tonight. => subjects of the sentence Ex: You can work on the project with John and me. => objects of the sentence. Ex: Me and Laura stayed up so late. => incorrect use of "me" instead of "I" and impolite form. However, this is a common mix-up!