TurboTax won't give me the Child Tax Credits

there are a couple questions you could have answered wrong under My Info or Personal Info.
If your child was away at college, count the number of months away as having lived with you. The correct answer to claim the person is to say "the whole year". This will indicate you supported the person the whole year, thus it will be entered on your return correctly showing up as a dependent.

Or the one that says did your CHILD pay more than half of their support. It's not asking if you did.

If you can't get your child to qualify try completely deleting him and then re-add him. That sometimes will clear something out.

If your child was born during the year (even on Dec 31) is considered to have lived with you all year. When it asks about how long they lived with you, be sure to answer all year (pick the top box for the Whole Year). You will have to have their SS# before you can file.

Check and make sure you didn't accidentally check the box that says you (or your spouse) can be claimed as a dependent on someone else's return. You can't claim any dependents if you (or your spouse) is a dependent. People are saying that if you transferred from last year then one of the spouses came over with it checked that you can be claimed.