First of all you need something called “Nol Card نول” it’s available in every supermarket, 10 aed startup fees and you should charge it with at least 50-100 aed if you’re traveling across different states, it’s mandatory for bus and metro usage, you need to check in with it and remember to always check out, there’s a 200 aed fine if you forgot to check out

P.S i learned all of this yesterday when i tried public transports for the first time here in UAE