the term popularized by Jacksepticeye is generally used to curse out a nonexistent thing (i.e. life) or a living being (i.e. a jerk) to an insurmountable extreme, usually screamed at the top of ones lungs.
I was playing Unfair Mario, and I died so many times that I couldn't help but shriek "FUCK-A YOU, GAME!!"
Fuck a biscuit is what you say when you've been to too damn many Waffle Houses over a period of stay in the American South.
We been on this tour bus since Williamsburg, last date in Shreveport. I been eating grits and waffles and all kinds of pork all summer. To hell with a collard green and fuck a biscuit.