@lcolantuoni14 said "where he resides: AS far as where he lives - obviously at college".
In that case, he cannot be your dependent. He can file independent. The support question is moot. To be your QC dependent, all 3 rules must be met (age, residency, support).
But, that also means he cannot go back to being your dependent for 2022.
He cannot deduct his living expenses during the internship, if he was a W-2 employee. If his pay was reported on a 1099-NEC (instead of a W-2), he is considered self employed and the answer MIGHT be different (but probably not).
If you are a regular W-2 employee, you are no longer (effective 2018) allowed to deduct mileage and other job expenses. Even when you were allowed to, it was only an itemized deduction subject to the 2% of AGI threshold.
Despite the 2019 date on the other post, it was really answering a pre 2018 quesion (there was a 2019 transformation of this forum and the old questions were migrated en masse).
