Download and run the free version of EtreCheckPro, from > https://etrecheck.com/en/index.html
Then post that report in this thread using these instructions: How to use the Add Text Feature When Post… - Apple Community
If something is buried it might not turn up in that report, but there might be something we could spot that would help determine if Streem is legitimately on your Mac or if it's an indication of malware.
Meanwhile, I'd strongly suggest that for now you not access any financial accounts from your Mac, just in case there's a keylogger hidden, and on another device immediately change your passwords to any such accounts, or to any other critical accounts that would be harmful to your life should someone gain access, including your Apple Account.
For complete peace of mind, you may want to just erase your Mac and start fresh.
Regards.