How to recharge and replenish in the wild?

The problem is the macronutrients -- Getting enough energy. If you expend 3500 kilocalories per day (typical) it is very difficult to maintain sufficient energy substrate on the two pounds of food per day many people use as a target. You need to emphasize fats and oils (9 kc per gram) over carbs and proteins (4 kc per gram) for energy. Many people do not like that much fat in their diet, and a commonly reported side effect of altitude is a dislike of fatty foods.
For trips of a week or less micronutrients are not a concern. Your body has sufficient stores to hold you that long, and the B complex and C vitamins are found in most backpacking fare.

On a hot day cool water, even cold water, is good. It will cool the core.

Most people, upon reaching their intended camp at the end of the day, immediately drop their pack and collapse for a half hour or so. Bad practice. To prepare for the next day's hike you should instead drop your pack and take an easy quarter mile or so walk back down the trail (or up trail, whichever you prefer). This is a cool down and gets the metabolic waste products out of your muscles, hastening their recovery. Then immediately drink an electrolyte replacement drink with lots of carbs. High glycemic carbs are preferred here -- one of the few times high glycemic is preferred. Also consume a SMALL amount of protein. Not a protein shake. You want more carbs than protein immediately post hike. Push protein at dinner in about an hour or so. This will help replenish glycogen stores, stop catabolism, and begin anabolism and your muscles will replenish and recover overnight.
Monitor your urine color and drink as needed to stay fully hydrated.

Force yourself to eat if you are not hungry.  You need calories even if you have no appetite.  If you do not eat you will seriously bonk tomorrow.