Instead of requesting “proof of God”, this is what you should be doing, “prove that there is no God”. Then, you will understand why the ‘proof’ lies ‘beyond death’.
For some, they may have spiritual encounters (of any sort) which has caused them to believe in God even ‘before dying’. These cannot be substantiated in the ‘way you require’ but has to be taken in ‘faith’.
In the end, it’s just my words against yours.
We’ll see ‘who was right’ (whether ‘theists’ or ‘atheists’) in the ‘afterlife’.
Make thy choices ‘wisely’.
The Bible reads:
“For the choir director. A Psalm of David. The fool has said in his heart, “There is no God.” They are corrupt, they have committed abominable deeds; There is no one who does good.” (Psalm 14:1)