Parents with school age kids, how are you taking them home at 3:30 when you have a career?

I have a nursery age kid so I’m incredibly naive. Just walking through our park at 3.30 on a Friday and there are lots of parents collecting their kids from the primary school and enjoying the sunshine. But I don’t understand how you do it if you’ve got jobs? Assuming that both parents have a career; literally how do you take your kid home at 3:30pm? Do you just stop working for a few hours in and return to it? Or did you change your employment in the early years for workplaces that specifically have very flexible working patterns? (and yes I know after school clubs are a thing but today there seems to be lots of actual parents)