Getting back into the pedaling has been a process for me, too. As a teen, I'd just hop on at the start of summer and ride all day, never thinking about it. But a few years of not riding apparently added up! So, yeah, expect to build back up to it again. I don't need any carbs, really, but I DO need to supplement magnesium and potassium or I get cramps.
Steak, eggs, potatoes - fruits, nuts, berries and forage. Coconut milk and potent herbs and spices. Tea instead of coffee now and teeny amounts of kelp daily. Let's see how this does! Not really had dairy much, and gut seems better for it.