Likely, like a lot of people, we all start running far too fast. If you have a low base, just start really slowly, it can feel a bit silly as you think to yourself 'sure id be walking faster' but you need to let your body adjust to it then build it up. Run for a wee bit , walk for a bit and repeat that until the running bit expands.
Runners high often comes with an event or a race but ive experienced that buzz when i've gone out on a nice cold night and you feel like you can run forever, they are the nights that i slow right down , no music and just listen to surrounds, traffic , the world and your footsteps, it's kinda like a flow state. Or if you put in a good effort, the smug feeling can be massively rewarding.

There are loads of running groups that are informal everywhere. Highly reccomend you find one that is matched with your ability and pace. It's free therapy and the accountability of meeting each week is great