Cutting out sugar, caffeine and alcohol, when during cycle is best to start?

Almost 20 years ago (for other reasons) I gave up sugar, caffeine etc.. and after the 2 week mark I felt great, physically and mentally.

I want to do it again for a few reasons including maybe lessening Endo issues and symptoms.

I feel like there's always pain, fatigue, bloating and problems throughout my cycle, before, during and after my period.. it's all a blur to when I actually feel okay, I couldn't even tell you.

Does anyone know in regards to hormones and the likes when might be the best time to undertake cutting something out? I found the first couple of weeks difficult before with cravings and the likes but I can't moderate it so it's better to just cut it out.

I'll mostly like do sugar and caffeine (don't drink much so not an issue) I'll have decaf even though there's less caffeine but not 0.

Looking forward to any advice, or even people who have cut out sugar/caffeine and any improvements you noticed?