Like from above, you can use worldgaurd. Each world has a different list of regions, and to flag the entire world you're gonna wanna do

/rg flag __global__ tnt deny

This command will flag the entire world, denying players the use of tnt in that specific world

One way is to use world guard. Once installed world guard will produce a config file for each world. You can then go into that file and there will be something called the blacklist.txt. In the blacklist there will be information on how to disable items and you will be able to disable TNT for that individual world.

(Sorry for any formatting issues I sent this on my phone)