If your son correctly said on his own return that he can be claimed as someone else's dependent, then you should be fine to claim him on your own return and e-file as usual. If he messed up and said no one can claim him, then your e-file will be rejected and you will have to file by mail.
You go ahead and enter his information in My Info as a dependent and make sure that you also say that he was a student in 2023 so that you can enter any education credit you are eligible to get. The parent or person who claims a student as a dependent is the one who gets education credits.
https://ttlc.intuit.com/questions/1901172-what-are-education-tax-credits
https://ttlc.intuit.com/questions/1901172-what-education-tax-credits-are-available