Alevels psychology and sociology

The school i go to doesn't teach those subjects at an igcse/gcse level however I'm considering taking them as alevel subjects as i plan on going into jobs that,while alevels in these subjects isn't required, will very advantageous to have knowledge in those subjects.
So my question is can i take alevels psychology and sociology even if i haven't taken the igcse/gcse subjects for them? By that i don't mean will schools let me take the subject if I haven't done their igce/gcse, I've done my research and they will. My main problem is will i have missed out on learning a considerable amount of concepts and be behind compared to others who have taken the igcse/gcse for it and have to work extra to make up?

I think most people are taught as if it is the first time they are studying the subject because everyone at my sixth form who did those subjects were doing them for the first time.

hi! i did sociology at gcse and currently do it for a-level, whereas most of my class hadn’t done it at gcse. i wouldn’t say you’re at any disadvantage since the content i learned at gcse was basically just re-taught at a-level anyway, so you’ll easily be able to catch up with people who did it at gcse
that being said though, not sure if it’s coincidence or not but the people in my class who achieve the highest grades happened to have also done sociology at gcse, so maybe there’s some sort of advantage there, but there’s no disadvantage if you hadn’t done it x

Thanks for the info!

The school i go to doesn't teach those subjects at an igcse/gcse level however I'm considering taking them as alevel subjects as i plan on going into jobs that,while alevels in these subjects isn't required, will very advantageous to have knowledge in those subjects.
So my question is can i take alevels psychology and sociology even if i haven't taken the igcse/gcse subjects for them? By that i don't mean will schools let me take the subject if I haven't done their igce/gcse, I've done my research and they will. My main problem is will i have missed out on learning a considerable amount of concepts and be behind compared to others who have taken the igcse/gcse for it and have to work extra to make up?