Upcoming IVF question

What happens after the RE submits a treatment plan? We plan to do <a href="https://glowing.com/glow-fertility-program">IVF</a> for my April cycle. If my period starts the first week in April, is that when I'd start meds or before that? I know my RE office will go over this stuff but I am trying to prepare myself. Thanks ladies. I'll take any info you have to offer me.