Is it possible for an admin of this site to just change the BiggestSchnoz email to my gmail which is the one for this account and then delete this (BiggestSchnoz77) account? Otherwise can an admin tell me what to do? Perhaps message me a temporary password and once I’m back in my BiggestSchnoz account, delete this one? I don’t want to lose my premium subscription or my progress. Thanks for any help.
You'll need to contact support directly, though if you don't have access to the old email, they may not be able to verify it belongs to you
https://support.chess.com/article/4567-why-was-my-password-reset
You'll need to open a ticket with support:
https://support.chess.com/article/346-contact-us

Is it possible for an admin of this site to just change the BiggestSchnoz email to my gmail which is the one for this account and then delete this (BiggestSchnoz77) account? Otherwise can an admin tell me what to do? Perhaps message me a temporary password and once I’m back in my BiggestSchnoz account, delete this one? I don’t want to lose my premium subscription or my progress. Thanks for any help.