Welcome very new member. Good luck!
Please do remember that formulating a problem/question in a way that makes sense is in itself an integral part of a scientist's job. So don't miss out on the chances to practice your opportunities to formulate scientific questions. It is sometimes a little different than the language used in chatrooms. Plus, a well formulated question has greater the chances of getting replies that actually make sense.
To your questions:
1) yield = yield (actual) / Yield (theoretical)
2) number of moles = n = m/M (where m = grams of stuff and M = the number of grams that 1 mol of stuff weighs)