Hi, here are some tips:
First, put 1 person on the berry bush, and the rest researching.
When it's night time, pause it.(pressing space and then exit the game)

The next day, if you have 250+ food, don't put anyone in the berry bush. If you got enough tech, buy farming. But you don't need anyone to water the crops. However, now you should have some food now. Do this:
Avg Food per villager|Research:Farm
5|5:8
10|5:5
15|5:3
25|5:2
40+|5:1
70+|5:0
Just a tip.
And try to buy like that,
Farm LV2 -> Build LV2 -> Med LV2/Tech LV2 -> Tech LV2/Med LV2 ->Farm LV3 -> And now you don't need to worry about food!