My computer got virus, please help me?

Last week, i use my friend's tumb drive to save file into my computer. After that, i found out that my pc is effect by the tumb drive virus which is auto run. It make my folder cant view hidden file when i turn it to show hidden file. Also it dont let me to update my bit diffender software or if iwant to view the anti virus websitte. It show invalid server. So, how can i do now? got any other software to fix this? Or i need to format it? Please help me. Thanks u so much.