fsh test - on a induced bleed?

hello i am now preparing for my second ivf cycle if you have read my previous post.

They want me to do an AMH test which i know you can do at any time of the month . But because i have pcos idk if i will get my period this following month . They want me to on day 2 get the fsh test done. But again what if i do not get my period!?

I am getting super anxious because of the unknown . They want me to start the pill on the same day untill they tell me when to stop .

I was jusg wondering if there is anyone on here who can advise? If they induce my period will my fsh results be same to those results as a natural bleed? I am trying to get my head around it!

thanks