I'm 43, but when I was your age I worked for a agency doing custom software development for non-software companies, in an office. I retrospectively think that could have been some of the most meaningful time that I spent in my career -- in terms of having impact on the real world that I can point to, and growth and social connections. Also, because the people who ran the company had little experience of the business world: almost no meetings, no product managers (we just talked directly to our customers). Just about 15 software devs, some UX folks and a minimum viable management layer (who was also sales).
It was mostly 1-2 people per project for the lifetime of the customer, so you had a lot of leeway over how you built software, as you were going to be probably maintaining it for the rest of your time at the company.
But at the time I hated it: meh pay, chaotic work environment, micro-management of your time, FILLING IN TIMESHEETS, an open-plan environment which was noisy and distracting, no structured knowledge sharing, CI, testing or other grown-up software practices. I was very unhappy there and don't want to over-romanticize it -- but I wouldn't be the person I am today without that experience.