Streamer/Gamer 1G issues

Hello so I’ve tried everything to fix the issue it’s latency / Packet loss. My Internet to put into words is volatile never stable. It will get download speed 30-957 MBPS flex like crazy. My network is always congested. My plan should allow multiple devices can’t even run my Xbox alone smoothly. When I play around any other player it’s like lag. It’s packet loss and latency. Century Link should be installing Fiberoptic in my Nebior hood in January 2021. I heard it’s so much better gets less congested and it’s more stable. With as much money Comcast/ Xfinity makes You think they would be upgrading all the lines.