" I Can not Forget this School because this is where my past lies"
"I Can not Forget this School because this is where my past lied"
Which is More appropriate ?

I think the first one.

hello, the first one will the correct for sure as you can see that lies word is used in that sentence which means that your past is still there, while in the other sentence lied is used which means that your past was there present but is vanished now ...... ok hope you have understood and this answer helped you.