help for setting up a formula to calculate monster evolving in Summoners War

Hi. I want to make an excel file that I can use to calculate how many units I can evolve.
Basic info:
for a 2* (2 star) unit to evolve, it needs to be max level, and needs 2 other 2* units (of any level) to become a 3* unit
for a 3* (3 star) unit to evolve, it needs to be max level, and needs 3 other 3* units (of any level) to become a 4* unit

how I want the excel to work is like this:

A1 here I type in the ammount of 2* units I have
A2 here is the formula for how many 2* max level units I need to evolve those units

A3 here is the formula for how many 3* I will get from that
B1 here I type in the ammount of 3* units I have
B2 here is the formula for how many 3* mac level units I need to evolve the 3* units I have typed into B1, and taking the ammount of 3* units I got from evolving 2* units in A3
B3 here is the formula of how many 4* units I will get from that

I will also be having a formula for 4* into 5* but that one I is similar to the 3* one, so I'll be copy pasting that formula and adjust it for 4* instead of 3*

I have basic excel knowledge from school, and using it for simple things from now and then
I know how to use the standard commands like multiplying, adding multiple numbers together and so on.
I do not know how to make advanced formulas like I am trying to do now