Do you have taxes payable? What province are you in? Which version of TurboTax are you using? Is it Online or is it the CD/Desktop edition?

I am using the Standard Version and I am in Quebec. I have tuition money but it won't let me claim it in my deduction for 2018

Do you have taxes payable? Are you getting an error message?

I don't owe any taxes and I am not getting an error message

The tuition credit is non-refundable. You only get the credit if you have tax payable. It will not add to a refund. So if you are already getting a refund, you won’t get the tuition credit, instead it will carry forward to future years to be used when you do have taxes owing.