Would it still be a bitcoin wallet and if so what can I do?
That depends on where your partner got it from, "
wallet.dat" file can be from any of Bitcoin's forks so it can be an Altcoin wallet file.
Or even a fake if he just bought it from somewhere.
Would it still be a bitcoin wallet and if so what can I do?
If you can spare about 500GB of bandwidth:
Install Bitcoin Core 27.0 (
link above this forum's menu), launch it.
Set your preferred settings (
enable "pruning" if don't have enough storage) and immediately restore the wallet.dat file with "
File->Restore Wallet...".
Then let the node sync and your Bitcoins should be displayed once it reached year 2010+ blocks.
Reply if you encountered an error during the restore wallet process.