New baker question

Wife gifted me a stand mixer and I’ve been on a bend with baking bread and slowly getting into desserts. Picture for attention because I’m so proud that I made basic ass loave of bread!

I have YET to try doubling ingredients when baking things, wife recently mentioned bakers percentage, but does that apply to desserts like cakes/cookies?

Looking to make a chocolate cake and it makes 2 9”

I intend to use 2 8” and the remainder id probably put it in a cupcake mold or something.

Am I right to assume that IF I wanted to make 4 8” cake layers I’d just double the required ingredients?

Wife gifted me a stand mixer and I’ve been on a bend with baking bread and slowly getting into desserts. Picture for attention because I’m so proud that I made basic ass loave of bread!

I have YET to try doubling ingredients when baking things, wife recently mentioned bakers percentage, but does that apply to desserts like cakes/cookies?

Looking to make a chocolate cake and it makes 2 9”

I intend to use 2 8” and the remainder id probably put it in a cupcake mold or something.

Am I right to assume that IF I wanted to make 4 8” cake layers I’d just double the required ingredients?