Just like any other job, entirely dependent on your particular unit/department and manager. In the US Fed gov't there's a huge difference between working for CBP, civil Marines, and NASA, just to name 3 random agencies.

The difference with the feds is that you get a basically predictable paycheck (as long as Congress does its damn job), health benefits that make life habitable, the best possible version of a 401k around (TSP), and you're extraordinarily unlikely to get downsized.

Last I checked, the plurality of civilian federal employees make GS-13, which in 2023 was between $98k and $153k depending on where you were located, and how long you've been at that pay-grade. It's not an overwhelming plurality, butnit's not unusual to promote into a GS-13, and then hang out there for most of your career.

Retirement is a three-legged stool: your TSP (aka 401k), Social Security, and a small pension. People hired before 1985 were the ones who got the sweet fat pensions, but it doesn't work that way anymore.