as mentioned before, the competent crew course doesn't really involve that much, most of it you will quickly remember from dinghy sailing. Here is a quote from the RYA website:
Pre-course experience and knowledge - none.
Course content - Knowledge of sea terms and parts of a boat, her rigging and sails, sail handling, ropework, fire precautions and fighting, personal safety equipment, man overboard, emergency equipment, meteorology, seasickness, helmsmanship, general duties, manners and customs, rules of the road, dinghies
Ability after the course - Able to steer, handle sails, keep a lookout, row a dinghy and assist in all the day to day routines
You will go through all this and far deeper in the Day Skipper. Don't forget, the complete Day Skipper is a theoretical course (evening class or guided self study) and then afterwards a practical course. Yes, this is the course where you will learn about tides, navigation, passage planing, pilotage etc.
A good sailing school (I did my VHF course with) in your new neck of the woods is Ashore Sailing
One of there venues for their theory courses is in Quorn, that is a part of Loughborough ! The Rutland Sailing Club and the Rutland Watersports Center both have practical dinghy courses, if you are interested.
This link should give you a list of Day Skipper Theory courses close to Loughborough. Have a look at the different schools and check out their venues which can be different from the main office:
Find A Training Centre | Learning | Courses & Training | RYA
Best sailing areas ? For me that is still simply wherever I have my boat. Love Rutland (where I tried Rockhopper out first), the West of Scotland was amazing (but watch out for streams/tides and the submarine training ground off Troon
), Crouch is great because it's close to where I am now living with my family. I think you'll get my idea ...
I am still at a very early stage of a hopefully long and fruitfull journey ...