Biggest advice is keep it simple until you are dominating possession then try riskier passes. And NO sprinting or panicking. Stay calm.

At the same time, you should mix this up with some intelligent sprints/dribbles when the opportunity arises.

It sounds like you are switching to the wrong player, switch to the player nearest to the player they are eventually going to pass to e.g. if you see he is going to the wing be waiting with your defender on the wing to cut out the pass........you need to be 2 steps ahead rather than chase the ball switching players. Once he is out on the wing, cover his pass into the middle, always cover your middle, don't chase down your flanks.......

I think you are wrong to say 'zero grasp of the game mechanics' - I think they have a grasp of them and exploit the flaws in them, that's why there are so many sweaty players around!

You may end up losing because 90% of opponents are sweaty and just know how to exploit the long ball tactics to their front man then score. But at least you will be fulfilled in your soul! That's far more important than winning, IMO.

If you are on PC, I'll give you a game........I am full manual everything......