I think i was RATted, need help

Hey, so today I was on Minecraft when suddenly my laptop started joining and leaving servers very quickly, opening blank Google tabs and preventing me from shutting my laptop down. So, I unplugged it. Now I have my Wi-Fi off and I'm doing a full MRT scan. After investigation I found absolutely zero events that happened in that time period, however my Windows Defender quarantined a file i downloaded yesterday as soon as it was installed, let's call this file CS (it was cities skylines) Now I did NOT run anything inside the RAR file. I only extracted and scanned the file which have me 41/71 detections, all are Trojan etc. The quarantined file shows "Trojan: Win32" and says it can allow someone to remotely access my PC. Now I wonder, I didn't run anything, I couldn't find any background processes, so what the hell happened? Is it a Trojan/RAT or just a bug? (doubt) Well, I also did download another file from the same site I downloaded CS. I did run it, but it's been on my computer for months. I deleted any sketch files from my computer, I still am scared and don't know what to do. NOTE: I'm not condemning to download any cracked software. Just wanted to slip this in because it won't allow me to post this