Question

(3n^2 + 2n + 4)(2n - 1)

Answer 1

If you've heard of FOIL, then don't use it here.
FOIL is used to multiply two binomials together.
Here you are multiplying a trinomial by a binomial.
The method for multiplying polynomials in general is to multiply every term of the first polynomial by every term of the second polynomial binomial. Then collect like terms.

Answer 2

The trinomial has 3 terms. The binomial has 2 terms.
After multiplying each term of the trinomial by each term of the binomial, you should have 6 products. Then collect like terms, and most likely you'll end up with fewer than 6 terms in the end.