The short answer is no to the gloss layer and no to the white layer in your particular case.
There is plenty of discussion in this thread, as well as a helpful step-by-step tutorial:
https://guitarpcb.com/community/topic/just-finished-nostalgiatone-dsotm/
You can also use AI, like ChatGPT, to assist with art program-related questions. While it’s not perfect, it can be much faster at answering specific questions than sifting through a YouTube video—although that’s another alternative. I am certainly not an expert in the art department.