To install a new modpack on Technic Launcher you first need to visit this page and browse the modpacks
Once you have found a modpack you like install it like this
- Open your technic platform
- Click add new pack
- In the box paste the platform url found on the modpack page
- Click "Add Modpack"
- Log in and allow the pack to download
- Go to multiplayer and select the server that will automatically be there!
Watch this video as well