My son is 18 he had a job in 2019 how do I add his w2 to my return Bc he is my dependent I paid for all his living expenses in 2019

If he is your dependent, you claim him as a dependent on your tax return, but you don't claim his income.

He files his own return, but he must select "Someone else can claim me" and "Someone else will claim me" when he starts his return.