It might be a silly question but for example if a Bitcoin wallet in Bitcoin core is lost, is it ???possible to make/recover the original wallet file?
My sense is that it is not possible because the password/signature is for verification , not for source creation.
The private key you have encrypts the wallet file you created, so if a SCAMMER finds your file, they need the password to decrypt it.
In short, you will need the file (wallet.dat) and password to get the private key to spend those coins.
But if you use SPV wallets
[1], you will most likely get seeds, those seeds (alone) represent the private key that enables you to spend bitcoins.
Overall, BitcoinCore is not a wallet for beginners who don't have any background in Bitcoin or computer, it's a full node wallet, and it needs to sync the entire blockchain (more than 300GB) so if privacy isn't your first goal, use opensource SPV wallets.
[1]
Simplified Payment Verification (SPV) - BitcoinWiki