Stop links opening new tabs

Say i went into google and searched something, when i click on a link it opens a new tab. I don't want it to open a new tab, i want the link to load on the same tab. I accidentally downloaded a virus and although i've fixed everything else, which seemed like it would be harder thi shas proved the hardest thing to do, and i think it should be easy to change these settings. So, after that feedback my final question is: How do i stop new tabs from opening when i click on a link? Trust me, i've tried a lot already.