My father had said several times he had around 50000 btc when he first heard about it a while ago, and I don't know if they are fake btc or something but I want to access the wallet(s).
-snip-
I found 3 folders: "Electrum-btcp" "Electrum" and "ElectronCash" and they are all empty,
Chances is, your father meant he has "
50000 BTCP".
Anyways, looking for his backup is still worth it.
And speaking of backup, any of those Electrum variants (
One for Bitcoin, two for Altcoins) requires a "
seed phrase"
to be written as backup before the user can finish creating his wallet.
So look for papers with words written on it (
12 words by default) which should be the seed phrase that can restore his wallets(s).
If you found it, set an offline PC install Electrum and go restore it to the new version via "
Standard->I already have a seed" option.
Check the addresses (
View->Show Addresses) if any has balance.