If your combined GVWR is over 26,000 pounds, yes you need a Class A non-commercial license.
https://www.dps.texas.gov/DriverLicense/dlClasses.htm
You will be tested on setions 14 and 6
https://www.dps.texas.gov/internetforms/Forms/DL-7C.pdf
Then there is the skills test.
The first time you take the written test a clock starts. How long that clock is I do not know.
If you search on line, you can find practice tests. Without studying I failed, but was real close.
Once I get my camper out of summer storage (Dealer), I will pick up practicing and studying. I do plan to post my steps on getting one, once I can start the process.