Question

how do you unfoil

Answer 1

If you have the four FOIL terms, you would use a process called Factoring by Grouping

In short, group the first two terms together, factor out the GCF, group the second two terms together, factor out their separate GCF, then finally factor out (hopefully) a common binomial factor.

This is hardly a lesson in how to do it, just a summary of the steps. You should be able to search online for Factoring by Grouping and get what you need.