First time travel tips

This is our first time going to cancun, 2 of us 21F, what are the things we can do in budget? what should we know? Things we are not supposed to do? How to dress? How’s the crowd? What should we be alert of? Things to know before going? Safety wise what should we keep in our mind? And how’s hotel Cyan? Any tips to help us with our trip would be greatly appreciated! Thank you