What is the legal age in tx to get birth control pills and how do you get them?

No cut off age. You can get birth control pills as long as you have started having periods. You need to see a doctor and get a prescription because birth control pills can be dangerous for a small nber of women. You can go to a women's health clinic or planned parenthood.
Rx by GYN or PMD. I don't believe that there is a younger age limit that one has to reach before a doctor can prescribe the pill in texas. One would obtain the pill by seeing your family dr. Or your gyn. It is unlikely that a pelvic or breast exam or pap test will be needed.