Proxy Network usage

Hi,
How much GB I need for 30 Days of botting in average?.

Depends on the Bot software. Which one do you have?

FollowPlanner

I have never monitored FollowPlanner's traffic, so no experience directly, but FollowPlanner is a web based bot.
One of my accounts via another web based bot consumed on average 250-300 MB per month.

Daily follow/unfollow, liking and scraping users, no postings.

Everything depends on how much actions you do with your account. Daily scraping users and uploading media consums a lot of MB.