Cannot stress this enough: if you think you have Long COVID: DO NOT EXERCISE.
I know it feels like you can, but post-exertional malaise means that the damage you do when you exercise you may not feel for a day or two. Exercising makes you WORSE. It causes damaging chemical reactions. And the first six months (when you probably haven't got a diagnosis) are your best shot at recovery, but only if you REST. Completely.
I despair when I see people say they think they have LC and then go jogging.