Texas is a big state, so you will be required to drive a car around with GPS. You will need GPS, trust me. There are many places to check out, but it is impossible. It is big! I would wait for COVID storm to die out first and hopefully, vaccine will contribute to it. In major TX cities, You will have to wear a mask when you enter any place.
In DFW, stay away from toll freeways. You can't drive without a toll sticker or the camera will take a picture of your license. If you want to visit Dallas area, stay away from Oakhurst. It's not safe. DFW has its own railway called DART if you plan to go to Dallas downtown. DART is awesome to use. Go to Dart. org.
Sixth Floor Museum at Dealey Plaza
Dallas World Aquarium
Dallas Zoo
Fort Worth Zoo-- TOTALLY RECOMMENED.
The George W Bush Presidential Library and Museum
Dallas Museum of Art
Reunion Tower
Fort Worth Stockyards- they will let you ride a mechanical bull. Lots of fun. You can go to their website. They have schedules.
Kimball Art Museum- my favorite art museum
Six Flags at Arlington
AT&T Stadium- check their schedules for tours.
Since you're Indian, there is a Indian/Pakistani community in DFW, especially North Dallas. Lots of places like restaurants and markets. Try India Bazaar grocery. They're everywhere! You will see lots of East Asians, too. Most are from Nepal, Korea, Vietnam, etc. I miss going to Daiso Japan in North Dallas. DFW is extremely diverse. If you go to east Dallas, you will see some Muslims full of hajib.
In Houston, it's a crazy city with horrible infrastructure. Watch out for trucks. Stay away from toll freeways, too. It is about 4-5 hours drive from Dallas. 4 hours drive from San Antonio.
Houston Museum of Natural Science
Children's Museum- if you decided to be a kid, you can play there!
The Health Museum
ArtCar Museum
Houston Zoo
Museum of Fine Arts
Galveston
San Jacinto Battleground site
Austin.. Austin.. ha! Yes, It's full of weirdos pretend to rub on each other and protestors! Public/garage parking is expensive, so save some money if you must. Try Capitol Visitors Parking Garage. it's a bit affordable, but you will have to do lots of walking. You will notice the homeless people sleeping under the freeway bridge and areas. You will have fun watching protestors on Congress Ave all the way to the Capitol building. There are so many places to check along Congress Ave and the 6th street that I can't possibly list.
LDJ Presidential Library
UT at Austin
Bullock Texas State History Museum
Blanton Museum of Art
Capitol Building
Texas Governor's Manson
Congress Ave. Bridge
Bat Observation center is next to Congress Ave.
Crepe Crazy two locations by Deaf owners
San Antonio is all right. if you want to see the Alamo, go for it. Don't expect the Alamo to be big... Just warning. lol
Riverwalk
Historic Market Square- Mexican Shopping district
Witte Museum
San Antonio Zoo
San Antonio museum of art
Bracken Cave Preserve
Cascade Caverns
Cave without a name
Natural Bridge Caverns