What's the main difference between "Muslim" and "Islam?"

If I say "wait for his turn" instead of "wait his turn", does it sound weird? How are they different?

You can say "wait for his turn" instead of "wait his turn". "Wait for someone's turn" is the original phrase, so "for" is omitted in "wait someone's turn" to make the phrase shorter. Therefore, both of these phrases have the same meaning.

Is the phrase "Nails scratchin' my back tatt” some kind of metaphor?

"Nails scratchin' my back tatt" is actually an example of a sexual innuendo. The rapper is alluding to the act of sex, describing the action of when the woman scratches his back (or back tattoo) when they are having sex. You will notice other context clues when looking at the song title ("Bad Things") and listening to the rest of the lyrics, which also describe the same act in other ways.

What does fellas mean ?

"Fella" is short for the word "fellow", which is another word for man or boy. The word "fellow" is pretty old-fashioned and generally only used among older people. "Fella" is more commonly used today, and the term "fellas" is often used among guys to refer to their other male friends.

What does "strand" mean here?

The word "strand" is a verb meaning to leave (someone) without the means to move from somewhere, usually because of a problem with transportation or money. So in this video "stranded" means if you're left stuck on an island, without means of leaving. Ex: He left me stranded in town with no car and no money for a bus. Ex: If the tide comes in, we'll be stranded on these rocks. Ex: Hundreds of people were stranded at the airport because of the storm.

What's "real-time" mean and when's it used?

"Real-time" means the actual time something happens. It's usually used in relation to computers, so something happens or is shown at the rate the computer processes information. Ex: We're gonna have a real-time meeting online. Ex: The researchers see the data in real-time while the experiment happens.