I've had the following suggested to me:
Cinnamon
Ovasitol
Magnesium
D
Fish oil
Chromium Picolinate
a B vitamin
A prenatal
a probiotic

I will say any time I try to take all of this I get really really sick. To the extent that I currently can't swallow anything bigger than my tiny little prescriptions without gagging. I would ease into a supplement regimen, maybe adding one a week? I'd also talk to a doctor, nutritionist, naturopath, someone about when to take everything. Also quality of supplement can be a big factor with regards to effectiveness!

I use hair, skin, nails by it works and legit works, also use Nixon System

Hi vitamin D definitely, E for acne and hair loss, and if ttc you can start a prenatal vitamin as well.