Yes, office / microsoft 365 is a single login to outlook, word / excel etc, share point and one drive and who knows what else.
i've used outlook on and off for 20+ years - it's basically an e-mail package with calendar built in. like all these things, it's got the usual features that microsoft think will be useful, multiple but not obvious ways of doing the same thing and so on.
the occasional refresher course in the likes of word / excel is worth doing - they add new features, or change the way you do things, every now and then.
organisation i work for is in the process of migrating from 'box' to share point and it's all been a bit painful so far. next step is supposed to be migrating from huge network drive/s to share point as well. blargh.
share point is a bit of a pain in the tail - the complicated bit is setting up permissions to folders (i need to have some folders that people outside organisation can get at, and it's all a bit complicated) and setting the right people up with access to view / edit and so on. the theory is it's all more secure than e-mailing a file to a lot of people who may then forward it to others, or edit it which means there's multiple versions of the 'same' document floating around.
once you've got it set up, it's not that much more complicated than copying files from one computer drive to another. although sending a file to someone else is more complicated - if i've got it right, you can't just attach a file to an e-mail, you have to share a link and make sure you've set it so that person has access to it.
and then there's one drive which is like share point but different - i'm still at the stage of ignoring it in the hope it will go away, but i'm probably going to have to deal with it some time.
in terms of training, have you looked to see what local adult education (if there's any of it left where you are) do? mum-tat did a handful of courses with lewisham adult education when she first got a computer (she had a home computer before i did - can't remember which of us went on the internet first) but that must have been some time towards the end of the last century... and you may be looking for something beyond the most basic of stuff.
have a vague recollection that morley college near waterloo used to do some one day / half day courses - not sure whether they still do, or whether they are going to be closed for the summer now.
if this is for a charity, there are a lot of organisations out there who push training courses to the charity sector - although the quality / value for money of these can vary.
there's a lot of online videos out there (microsoft's own, linkedin seem to have some (although not free), and there's stuff on youtube which can of course vary in quality) if you can't find anything real world, but you can't ask questions with them.
Reading university used to have a lot of IT training stuff online, but it seems to have gone - i'm not sure whether it should ever have been made public domain, but it was handy while it lasted...
