Honestly, there is no way to choose this, it is entirely a gift of nature. When you hold your baby, you will realize boy or girl doesn't matter at all.
There is no special diet or timing that can decide the gender. Just focus on balanced eating to keep your sugars normal, a healthy baby is all we need.
Scientifically, gender is decided by chromosomes during fertilization, which is completely random. Please don't trust any myths or babas, focus on a healthy pregnancy.
Uff, my family also used to talk about this. But scientifically we can't decide it, and legally too we shouldn't even think about it in India. Just eat healthy and pray for a safe delivery.
I had thyroid issues so my only focus was regular checkups. There is no scientific way to decide the gender, so just follow your doctor's advice for a safe pregnancy.