Lower speed then purchased and connection drops

Hello,

My plan is for 1gig of speed but recent speed tests across all my devices are showing around 90mb download speed and similar upload speed. I have tested this on multiple computers, reset my router and personal modem many times, and updated firmware on the netgear router. I have noticed that the xfinity leased modem and my netgear router are both advising slow download speed when tested. I have also noticed significant issues across all devices loading websites and videos. Finally today I have experienced frequent drops in connection on my devices. Does anyone have any experience with this and know any fixes I can try. I have had no luck with the troubleshooting assistant.