I've had rattles for the longest time, it slows your stamina regen quite a bit, my character is low and I'm sure later I can buff my stamina but still it doesn't help. Is there a cure or do I just need to rest/sleep or something.

Use a shrine, spell, potion, or vigilant of Stendarr to cure your ailment.

First! :intergalactic:

Pray at a shrine, the easiest one for you to find, is in Whiterun. You may be familiar with Heimskr the screeching priest outside Jorrvasker. There is a small talos shrine there, press on it and it will cure you.

Cure disease potion or a shrine.

Receive blessing in any town at a shrine will cure all diseases. It's the cheapest and easiest way I believe.

Cure Disease potion, or Shrine of (insert divine here).