Hi ArthurSmith-8361,
First, I want to say that I hear you. It sounds like you have been dealing with an incredibly overwhelming amount of stress, both with this computer and in your personal life. Having your hardware constantly fail and feeling like your privacy is being invaded while you are already going through a difficult time is incredibly frustrating and exhausting.
Reading through your detailed experience, I want to address the most critical issue you mentioned. The "support agent" who connected to your PC remotely, ran command prompts from the public domain, and the unsolicited calls you are receiving to "help" you, raise massive security red flags.
It is highly likely that you have been targeted by Tech Support Scammers. These are malicious actors who set up fake support numbers, pretend to be Microsoft, hijack your activation, and purposefully mess with your system settings to make you feel like your PC is fundamentally broken. Official Microsoft support will never call you unsolicited to fix your computer or demand to remote in unprompted.
You are not crazy for feeling like your communications are hijacked or your system is out of your control. Because unauthorized individuals had remote access to your machine, they likely installed malware or altered your network routing. This completely explains why your USB ports are failing, your drivers won't install, and your software is behaving erratically. Your current Windows installation is compromised and can no longer be trusted.
Here is my strongest recommendation to help you regain your privacy, security, and peace of mind:
Disconnect your PC from the internet immediately. Do not let anyone remote into your PC again.
Secure your accounts: Use a completely different, safe device (like your cell phone on its cellular data network, not your home Wi-Fi) to change your banking, email, and Microsoft account passwords immediately. Turn on Two-Factor Authentication for everything.
Complete Clean Wipe: The only way to be 100% sure your PC is yours again, and to clear out whatever those fake agents did to your system and license, is to completely wipe the hard drive. You will need to reinstall Windows from scratch using a USB drive created directly from the official Microsoft website (using the Windows Media Creation Tool on a clean computer).
Please take a deep breath. You haven't walked into hell, but you have unfortunately crossed paths with some very real, very malicious online scammers. You can take back control by wiping the system clean.
If you are ready to do a clean installation to secure your digital life, please let me know and I will provide the safe, official steps.
Tracy.