This is absolutely nightmare for any investor. You have to read these things about security when you make a new wallet. If you don't have backup file and you don't remember the password from that file then there is no way. It's very sad but it's true. If you new and not familiar with wallets, choose metamask for convenience(not huge sums) and hard wallets for storing long term offline. As for mobile and web wallets they have a lot of security issues, be careful.