I guess I ought to quit horsing around and give a serious answer.
There is no such thing as a Texas gunsmith certification, though it is possible to be a certified gunsmith in Texas.
I am not certified ( as a gunsmith, at any rate ) for example, but have been a gunsmith in Texas for thirty years or thereabouts.
Taking a course in college is a good way to get a start, and I would like to encourage the young man to do so. - He's right about that being the best way to get started as a gunsmith.
For my part, I kind of accidentally fell into gunsmithing in the 1980's. - I was a custom job-shop machinist and had developed the habit of hanging out at the local gun shop. I read a lot about guns, shot in matches and had accidentally gotten to where I knew something about them through the process of osmosis.
Having been a compulsive speed-reader since my teens, it didn't take me long to work through most of the available literature on firearms, including the slim stock of gunsmithing manuals. So, for a machinist, I was fairly knowledgeable about firearms, their manufacture and history.
One day the owner of the gun shop told me that he was going to have to let his gunsmith go ( reason unspecified ) and then the conversation moved to how much I was making as a machinist at the custom job-shop... Before I left the gun shop that evening, I was a new gunsmith - and they had lost their best customer.
I had a distinct advantage as such, being a master machinist and a speed-reader to start with, but of course I lacked experience.
I developed a method for educating myself, and gaining experience while treating my customers right.
There were several gunsmiths in the area, so I went around to visit all of them, and see what type of work each could do. With this information in hand, I could easily refer a customer who wanted something done that I hadn't done yet, to the appropriate gunsmith.
My idea was to never do something for the first time on a customer's gun. This is a policy that has served me ( and my customers ) very well throughout my career, and I will continue it for as long as I continue.
So I started buying firearms and working on them, thus giving myself some experience in the most common procedures. An advantage here is that firearms that need work are often inexpensive. Once I had done a good job of a particular procedure on my own gun, I would cross that procedure off of my referral list.
Once I had worked on a gun and had it working properly, I lost all interest in it and would sell or trade it in order to finance the next victim. My rule of thumb was to try to avoid losing more than 50 bucks on these deals. Quite often I came out ahead, but sometimes I really got hosed.
In every case, I gained invaluable experience that steadily accumulated.
Fortunately for me, the great majority of the customers that I had at first had really simple problems ( like a .22 auto that had quit working because it had been oiled regularly, but never cleaned ) - and when something came in that was beyond my craft, my list of local gunsmiths gave me a good place to send the customer so that their problem would be resolved. The customers appreciated my attitude about that, and would come back to see me when other problems came up.
If nothing else they could be sure to get a good referral, free of charge.
It didn't take me long to get to the point where I could handle just about anything that the shop's equipment could handle. There was no gun-bluing equipment for example, so those jobs were always referred out. - But after six months or so, over 90% of the work that came in was handled right there by yours truly, and I had to make a lot less referrals.
I have continued with this self-education system for around thirty years now and am still at it, as the shooting industry advances.
I bought an AR15 a few years ago, for example, along with the specialized tools for working on them, so that I would know my way around an AR.
Last year I bought a Mauser rifle and a NEGC double-set trigger, so I could learn how to install and adjust double-set triggers. My most recent victim was a Glock C29 that I bought so that I could learn how to tune up a Glock.
Using this system, I have obtained a nodding acquaintance with, and have fired an amazing number and variety of firearms. Whatever I buy and work on, I must test-fire of course so it's not all work, there is a good deal of fun involved as well.
Most gunsmiths wish that they were competent machinists... I had an enormous advantage in that area, and was fortunate in that respect. A good gunsmithing course at a university will go far in helping out a new guy who is not already a machinist. - If you have the time and money, I would recommend a basic machinist course as well, along with basic business and accounting courses.
The most significant new resource for new gunsmiths ( and machinists ) is YouTube. - But don't forget that the gunsmithing books will tell you a lot that is not on YouTube, most importantly about the attitudes and understandings that make a good gunsmith.
Also, it must remembered that YouTube is like Wikipedia in that it has lots of BS mixed in with the good information, and one must be ready and willing to separate the wheat from the chaff, there. - This is where the few available gunsmithing books have a major advantage over the internet as a learning tool. There's a lot more wheat in the books, and a lot less chaff.
Something about the gunsmithing books that is counter-intuitive is the fact that the really old ones are often more educational than the really new ones.
If one applies the Golden Rule to your relationship with your customers and sees to it that the learning process never pauses or rests, one can go far as a gunsmith and end up making a few bucks while having a lot of fun.
Your official two-pound maul, can of axle grease and big screwdriver can be obtained at most any farmers co-op or hardware store. It might be a good idea to bring these with you, on your first day in class at the university.
Good luck - and don't forget to have fun!