The difference between APR and APY  is pretty important to understand (but not difficult to understand) but the math can be a pain. Enter: The APR to APY (and back!) Calculator!.
It’s fairly straight forward, enter in an APR or an APY, confirm the number of compounding periods, and click on the button you want to do. The only limitation in the calculator is that it won’t do continuous compounding. You can just put some large number and that’ll be good enough because its rounded to two decimal points anyway. Another point to confirm is whether “daily compounding” is 360 periods a year or 365 periods, banks may use either one (it won’t matter which one you use because of how the calculator is rounding, it’ll give you the same answer).