"Searchmine" issue on '14 macbook air

So in the quietness of the covid'19 crisis, I went and installed, from online, a copy of Warcraft 2. Little did I know that it was infected. My Bit Defender did not warn me during the installation.

So now my browsers redirect my usual google home page to another search page. I tried to adjust it back using preferences, and followed online tips and suggestions... None were successful after system restart.

Please help me to get rid of this. In panic, I used other online virus/malware scanners but none of them detected anything, either. Thanks.

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