Depending on how much Bitcoin is on wallet.dat that you found, it's possible the cost to brute force the password is higher than Bitcoin value on fiat.
I would advice you should download Bitcoin Core to find out how much Bitcoin is on wallet.dat that you found.
Anyone can help me.
Not unless you know at least something about the password that you used (such as the length and type of characters used). It is an impossible task to brute force an encryption without having this information first.
And it's still not crack-able if the possible combination (based on what OP remember) is way too much.
When was the wallet file created? If your old computer was running Windows, that information is saved in the file properties. It'll give us an approximation of what version of Core you were using.
AFAIK Bitcoin Core is backward compatible and can open wallet.dat which created with older version.