No. Improper food and drink can cause irreversible damage.
If you have contained a sick, injured or orphaned wild animal, you have done the most important part. Close the box and keep it in a quiet place until you transport it to us.
Why you shouldn’t provide food or water:
Order of operations - Food is not the priority, and the animal is probably too stressed from pain and disorientation to eat . As with humans, eating is not part of the ER intake process, nor is it likely part of the initial treatment plan.
Temperature - We may need to restore the animal to a stable temperature before it can eat or drink.
Hydration - If the animal is emaciated, it may need to be carefully re-hydrated in a formulaic way before feeding it.
Nutrition - Each species receives a carefully tailored diet. Anything else could cause the animal real harm.