It depends on how your were brought up too.
I went to a grammar school. Everyone I'm still in touch with have fabulous careers. They stayed for a levels, went to uni. Most are doctors, lots of GPS and consultants, barristers.
For me, it was never even in my head to carry on with study post 16. What didn't help was that I was badly bullied all the way though school so I had no self confidence or self esteem.
But no one even spoke to me about staying for a levels. Not one teacher mentioned it. I felt like I was just something they wanted rid of ASAP.
My dad (my mum died when I was a child) never mentioned it. I did say about going to college but my dad just said what was the point, why didn't I get a job at a supermarket.
So I just worked shitty temp jobs in admin until I got married.
I did go back to college when I was 31. But because I didn't get a C in my maths GCSE (I got A-C in all others, I've just always been so shit at maths it was an E grade), I could only do a level
2 Btec. I did health and social care, within a week the tutors were saying i was wasting my own time and I should clearly do level 3 or do an access to university course instead but they wouldn't take me on anything higher than a level 2 without maths.
Long story short, I'm 41 now and have re taken maths gcse 4 times and never got that c, I've taken functional skills maths three times abs can't pass it. Countless maths courses (a lot of people who run these assume you need adult literacy too and speak to you like you are stupid, but I got A grades in English GCSE), one to one tutoring which I had to stop after a year as we just couldn't afford it anymore. There's no learning difficulties - I just can't do maths and I can't progress to study anything else without it so I stagnated.
I just do care work as I can fit shifts around my children.