If my son pay for more than half of their living expenses and other support? I'm the parent and I pay all his expenses.

I think you are trying to determine if you furnish over half of your son's support so that you can claim him as a dependent. Support would include things such as food, lodging, clothing, education, medical, recreation, transportation and other similar expenses. If you furnish over half of that, then that is one qualification to allow you to treat your son as a dependent on your tax return.

Other qualifications would include age (under 19 or full-time student under 24), living with you or their other parent, as well as income limits if they are over the age limit.

You can learn more about qualifying as a dependent here:

 Dependent qualifications