You need to have the title transferred to you and register it in your name. Here
is some information related to that — it will all be done via the TX DMV. There are some forms you will need to fill out. You will also need to insure the vehicle for at least Texas' liability limits. The minimum insurance requirement in Texas is $30,000 Bodily Injury per person, $60,000 Bodily Injury per accident, and $25,000 Property Damage per accident. Here
is more information related to Texas car insurance.
Best of luck and if you have any questions, don't hesitate to ask