Hi @dcndenis welcome to the /e/ Forum
So what steps exactlly did you take to “try to root” ?
Just to clarify, you took none of the steps to try to Install /e/OS on a Google Pixel 7 - “panther” ?
Perhaps [1] ??
Please can you explain in different words? Do you have platform-tools installed.
If the phone will boot to fastboot it should be possible to fix. We covered the ground above about the verified boot warning, you read and understood the link we deduce that you have done something to upset verified boot. The white Google screen seems to show when you still have regular Google Android but it is not bootable, neither to system
nor to Android recovery.
With the phone booted to Fastboot mode and platform-tools installed what is the response from
fastboot devices
Are you using a Windows or Linux PC ?
Edit, were you sure to [1] enable USB debugging before you started?
Unsure of your experience level, maybe this will give insight to recovery methods Flash Pixel Firmware: Android Flash Tool, Fastboot, ADB Sideload - TheDroidWin