How do I get T-mobile home internet into bridge mode

Speeds are awesome due to being close to a highway. 86 dwn 50 up is i write this. The "meat" of the gateway being inaccessibly is almost as lame as New Magenta.

This being the 1st time Ive ever purchased a network device that you cant manage has left me with strange feelings & questions that Im sure will be danced around. TMobile? Whos managing my HOME network since I don't have access to?

This 20+ year Network Admin would like to know