If you want to be a game warden, you better take biology. Also, it is very hard to get into because they stay in for life and Texas is having budget problems. Get some schooling and do some regular patrol first. Also, there in Houston you have a bagillion departments of all kinds. They recruit a lot from the regional academy there or you can get sponsored by a local department and go to Harris County Sheriff's Academy.
Some types of cops: police officers for cities, police officers for schools/universities and hospitals, sheriff's deputies for counties, constable deputies for county precincts, Houston Metropoilitan Transit Authority police, district and county attorney's investigators, state troopers, Texas Alcoholic Beverage Commission, game wardens and park police, etc