Hi, the best way to understand exponents are to always make them positive. Example, if you had a^-2 in order to make the exponent positive you have to do its reciprocal (A.K.A. flip it) therefore you'll end up with 1/a^2.
Let's start with the numerator, you have a^-3 b^-8, to make their exponents positive you have to move them to the denominator. So now you have 1/a^3 b^8 b^3 c^-4. Since the only negative exponent left is c^-4 we have to make that positive, which if its in the denominator and we flip it, it'll move to the numerator. Now we have a problem that looks like c^4/a^3 b^8 b^3.
Moving to the basics of multiplying and dividing exponents, when you multiply you add the exponents when you divide you subtract. In our numerator, we have c^4, well we don't have any other c's in the numerator to add exponents or have any in the denominator to subtract, so the final exponent for c is 4. In our denominator, we'll start with a. There's no a's in the numerator or the denominator so our final exponent for a is 3. With b is a different story, so we don't have any b's in the numerator which means we won't be subtracting exponents, but we do have to exponents for b in the denominator. Since they are both in the same place of the fractions you are basically multiplying b^8*b^3, and when we multiply we add the exponents so the final exponent for b will be 11.
Now, let's put the answer together. in the numerator we have c^4 and in the denominator we have a^3 and b^11. Your answer will be c^4/a^3 b^11.
Feel free to message me if you have any other questions. Good Luck!