Does the phrase "don't get sidetracked when I'm talking to you" make sense?
I hope the meaning is clear and you might paraphrase the sentence I have wrote somehow if it doesn't sound natural in English or something.
I've just found the word "sidetrack" in a book and want to get a better understanding of its meaning. In the book the word is separate, so I don't have a single example of its use. I think I can use it like that, can't I?
Here's another example I can think of, please tell me whether this one is also correct, "he isn't a good listener, as he gets easily sidetracked from me to something else".
Thanks for your attention! =)

Question

Does the phrase "don't get sidetracked when I'm talking to you" make sense?
I hope the meaning is clear and you might paraphrase the sentence I have wrote somehow if it doesn't sound natural in English or something.
 I've just found the word "sidetrack" in a book and want to get a better understanding of its meaning. In the book the word is separate, so I don't have a single example of its use. I think I can use it like that, can't I?
 Here's another example I can think of, please tell me whether this one is also correct, "he isn't a good listener, as he gets easily sidetracked from me to something else".
 Thanks for your attention! =)

Answer

Thats perfectly good english, however 'sidetracked' is more of a colloquial term.
You could use distracted to the same effect. One other small minor tweak would be, for the last sentence, 'from me ONTO something else', it's a really minor tweak but it sounds slightly more natural.

Answer

I think of sidetracked like a train that has gone off its original path - it went the wrong way. When someone gets distracted, they go the wrong way for a while. I believe that is where it comes from.

Answer

I'd agree that the phrase is understandable, but the word "distracted" sounds more natural in that context.

A common example with the word "sidetracked" that I often hear is:

"I meant to do it, but I got sidetracked along the way." 
Meaning: "I was going to do it, but I was distracted by something else (and didn't do it afterall.)"

It's often used as an excuse for not doing something, and is usually said with some regret.