It seems instead of starting TLauncher, its file was opened by one of your archivers (WinRAR, 7-Zip and so on),
we offer several solutions to this problem:

.......................................Windows.....................................
- Download the .exe version of TLauncher from our website https://tlauncher.org/en/
or
- Right-click on the launcher file -> Open with -> Java (TM) Platform SE binary
or
- Install Java again by downloading the installer from the official site https://java.com/en/

.......................................Linux.......................................
1) Install Java: sudo apt-get install openjdk-8-jre
1.1) Install after JavaFX: sudo apt-get install openjfx

.......................................MacOS.......................................

- Install Java again by downloading the installer from the official site https://java.com/en/