Office admin course

[Suntree32]

I was wondering if anyone had any advice, please.
I've been working in a shop since going back to work after years as a SAHM. I would like to work in an administration role of some kind, possible in a school office.
I don't have any relevant qualifications (I was a Civil Servant before having children 15ish years ago). I would like to do an online course to get me up to speed. Does anyone have any ideas for well regarded online courses? When I google there are so many options from companies like Reed, or they are prohibitively expensive.
Any help would be greatly appreciated.

A L3 Business Admin Apprenticeship may be a good option? They are for any age - my current apprentice is 39.

Also, some short courses are free, try this one:

https://distance-learning-courses.co.uk/courses/level-2-business-administration/

Thanks @Azandme. I've looked at apprenticeships before, unfortunately I can't commit to full time work at the moment, so courses I could fit round my current part time job would be great. Maybe in a few years, but I'm not sure I fancy being 50 and attending our local college (which all the local admin apprenticeships use).
The course that you linked looks good. I'll look into it properly. Thank you.