Lifestyle tips

Most jobs that give free food are relatively low paying jobs. If you are serious about gaining, you'll need a lot of money for food and clothes. So, I would choose a career that pays well. Just make sure it is a fat friendly career.

Mostly, it's a jobs involving a lot of sitting. Like call centers, or offices. Also, if you drive a lot, like truck drivers, it's involved a lot of sitting and stopping for snacks. That why the truck drivers are fat mostly. Any job not require to stand all day will do. Avoid jobs in restaurants and shops, I know people will say working as waiter will make you fatter, but that's not necessarily true, believe me I know. I was a waiter in a restaurants for over six years and almost did not gain much weight, but my current job has really made me bigger: I work in an office, with a lot of sitting in front of the computer, and with co-workers that like to make lunches for everyone. So basically that what I will recommend for someone like you. Such a job will definitely expand your waistlines.

I worked in an office environment for many years. During that time I saw many women and a few men gain weight, some quite a lot.
The company I worked at, in a "cube farm" hired young women just out of high school or junior college. They always started out slim, but nearly all of them gained weight, just sitting and working at their desks.
The sale people would bring in donuts often and during holidays, there were always tons of fattening treats available in the break room.

Coding. Learn to code. Even better, if you're in education consider computer-science so you have a firm grasp on the field and a good career path.

Data science is also useful for a good career.

There’s nothing physical in either sector (which are very linked) and eating and being sedentary will not hinder your work.

The skills you learn from entry level carry through not just corporately but in to self employment and generally you can expect a well paid career which leaves money for food and healthcare.

A job where "looks" aren't important. Perhaps as a model, or TV broadcaster.