your gonna need a periodic table for stoichiometry. you are also going to need to find the limiting reactant. hopefully somebody can make it clear how to do that because i am not great at it. once you find that you do this.

take the initial mass of whatever you are starting with. for example, you have 54.0g of Al. you then need to find the molar mass or how much 1 mole of Al weighs(the number usually underneath of Al on the periodic table) then you take the number of moles you start with which in this case is 1 which you know from the equation. then you take the number of moles of Cu that will be made in this case 3 and you also need the molar mass of Cu. now once you know all that set it up like this

initial mass(g)*(number of mol of reactant/molar mass reactant(g))*( number of mol of product/number of mol of reactant)*(molar mass of product(g))= total mass of product(g)

its hard to show on here but if you set it up so when you divide it is literally 1 over molar mass you will be able to see that units will cancel out and that is how you know you did it right. I don't want to give you the answer because it isnt really helping anyone if i do haha but let me know if you want me to clear anything up.