“Are you getting a refund?”
You are talking on the phone to you brother. He says that he just finished doing his taxes. You are curious to hear whether he's getting money back or will have to pay extra. You say this.
Are you getting a refund?
As you can see in the example above, "Are you ___ing" can be used to ask about something that will happen in the future. You're asking if something is already planned to happen. So you can ask this question after your brother did his taxes, but if you wanted to ask before he did them, you would say:
Do you think you're going to get a refund?
This means to get back money that you paid. You can get a refund for something that you bought at a store when you return the item:
I took those jeans back and got a refund.
Or you can get a tax refund like in the example above. You pay money for taxes to the government from each paycheck. At the end of the year, when you figure out the exact amount of tax you're supposed to pay, you may find out that you paid too much. In that case, you get a refund.