But the problem is that it redirect to a browser Hijacker.

Why? Did it hijacked anything in your browser?

Redirecting to a search page is something that some public DNS servers do when no record is found for the typed address. OpenDNS does it for example.

However, when you use Opera's VPN, the attempt to access a local IP address from within the browser instead is specially encoded and sent directly to the VPN server for routing data to the appropriate destination, just as all VPN address accessing attempts are encoded and sent to it. That prevents the system from automatically intercepting the local IP address and therby routing it locally. Unfortunately, Opera's VPN server has no ability to route the local IP data further since local addresses exist only on the local system and are essentially unknown and unpublished outside of it. Consequently, the access attempt through the VPN fails.

I think the problem is not in my pc but in the opera vpn

The problem is that you are using the VPN to access an address that doesn't exist outside of your local network. So the DNS server used by the VPN is redirecting you to its search page, like I said.

1. Check your browser for any add-ons or extensions you do not recognize and remove them.
2. Check your installed programs and see if there isn't anything suspicious that was installed lately (If there is, simply remove them).
3. Install any popular antivirus and do a quick scan (Majority of the providers do have free versions of their software). Or just use Windows Defender. It works well in most cases.
4. Install and scan your PC with Malwarebytes and Hitman Pro to clean most adware.

After this, in most cases, the issues of malware should be solved. If it doesn't work, sometimes Windows has a hard time removing the malware in normal mode, if that is the case, restart Windows in "Safe mode with networking." And try the following steps again.