Yeah the parkrun could be a good shout soon, be warned that its a race (of sorts) and so its very easy to get caught up in it. The positive side of this is that being fairly fit you’ll push yourself a wee bit harder than you would otherwise and probably suprise yourself. the negative is that you’ll hurt like hell the day after.
The usual response to starting out (that i ignored, injured myself, then went back to) is start slowww. For the first few weeks of runs you want to be going slower than you feel like you could/should be going, and also a lot shorter distance than you are capable of. At the moment your fitness way outstrips your bodies capabilities so you are just trying to acclimatise all of your joints to this new form of exercise and impact. If you just go out now and run to the limit of your fitness i give you about 3 weeks until you hit your first knee or foot related injury.
There are loads of plans for starting running on the web however unfortunately a lot of them assume you’re starting from low fitness, eg. couch to 5k. I looked through some of them to get an idea distances and frequency to run and went ad hoc from there. You’ll know when you start to feel comfortable and want to push up the milage.
Oh and a good tip that I got when starting out was: Time on your feet is key, dont worry about speed at the moment as that will come. Its a lot easier to injure yourself trying to go too fast.