minecraft FTB beyond help

so i have used the jigsaw client before and i wanted to be able to use it on my friends server but he runs his server with the FTB Beyond mod pack and it forces me to launch through the twitch app first then select FTB beyond in the minecraft play screen is there anyway i can use any sort of hacked client on this server of my friends? is their something im missing like a step im not doing? any help would be appreciated. thank you in advance.

You cannot use the regular hack clients. You have to search of FTB hack clients. I'm not fimilar with them but you can try google. However, I urge you to be very careful when downloading (as they aren't checked by trusted people of MPGH and can contain a virus)