Not necessarily. Our methods of hunting involved chasing down beasts for hours at a time. You’re looking possibly a whole village chowing down on a single deer.
The evidence is that, from what I’ve read is that we choose from a wider range of foods than even good diets consist of today. Amongst the foods back then would be called weeds today, like Dandelion stalks.
But, if you want to experiment, you could always cut back or increase your intake of proteins and see if that works for you.
Before agriculture the human diet varied wildly by location. People didn’t eat what they wanted to eat, they ate whatever was available.
But grains, dairy and other specifically agriculture-produced foods weren’t part of that diet. Grains were available, in some areas, but only seasonally and in relatively small quantities. Same with most other types of plant foods. Except in the tropics and arctic, what people ate varied wildly over the course of a year.
Probably not. Except in favored locations such as the Pacific NW, hunter-gatherers didn't live in villages. They lived in smallish bands, nomadic or semi-nomadic, that might come together seasonally into larger groups to exploit resources of particular areas. But most parts of the world will not support a village-sized sedentary population without agriculture.