Your question is a little vague and it is not clear what information you are looking for? Are you asking how to start a fly fishing guide business in Texas?
But as a general answer, no, I'm not aware of any fly fishing guide schools in Texas. There are guide schools offered in other states, primarily the Rocky Mountain areas such as Montana, and I think Orvis offers a guide school in the north east part of the country. So, if you want to attend one, you'll probably have to travel.
You'll need to research each school to determine if its program covers the areas that you are interested in learning. For example, some schools will focus primarily on drift boat rowing skills (which may have limited use in Texas), while other schools appear to be very specific to the types of fishing conditions that their shop supports.
Specific to Texas, the TP&W's hunting and fishing rule book contains details of most of the legal requirements to guide in Texas. That would be a good place to start.
Also, search the Bass Fishing section of the TFF, there are regularly postings asking about how to become a fishing guide. There is a lot of good information that has already been posted on the topic in that section.
Fly Fishers International certified casting instructor