Go back and forth and, more beef that you can pack a fork in
To go back and forth in “beef” is to fight or argue, but he plays with the meaning when he references a fork, making an allusion to beef being food as well.
He’s also saying go back to the start (of the rap game) and quit before things get too heavy, basically before people start having shit loads of beef with you.
Sticking a fork in something means that you’re able to destroy or defeat it. But having more beef than you can pack a fork in is having more problems with people/rappers than you can handle.
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