In reply to cfer:
I’ve done Cuerdon Valley, nice course, but yes quite tough. There are lots of different types of running, some you will enjoy more than others, go with your own flow and work out what you enjoy, road, trail, fell, solo or sociable, 5k or ultra.
You will get faster just by building strength, through more running, build your distance a little, but don’t feel you need to run longer races, this is a mistake that lots of people make. If you decide that is what you want great, but plodding around a marathon doesn’t make you a better runner than if you have worked hard to improve your 5k.
If you like the social side, parkrun is a great place to find out about local clubs or groups. I keep clear of runners world and things like ukrunchat on Twitter, they seem to mainly recycle bad advice.
The best shoes are not the necessarily the most expensive ones, they are shoes that fit, suit your running style and are not too worn. There is a specialist running shop in Preston, so support that.