I think the only answer that works here is 'doesn't it'. '
Hello, Asma, and welcome to the Grammar Exchange.
Ahmed is right that the answer is "doesn't it?" You can see this clearly by simplifying the sentence. We can substitute "this" for the clause "what you will be able to do at the end of the course" and "that" for the clause "how much time you spend on doing your assignments." This gives us:
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