How do people open another WhatsApp account on their phone? Is this done through QR code linking?
To open another WhatsApp account on your phone, you typically need a separate phone number. Some phones support “Dual Apps” or “App Cloning” to run two WhatsApp accounts. For accessing someone else’s WhatsApp, monitoring apps like mSpy can help by allowing you to track WhatsApp activity remotely (where legal). QR code linking is for WhatsApp Web, not account creation.
WhatsApp is a one-SIM-per-account kinda party. Want two legit accounts on one phone?
Install WhatsApp Business alongside regular WhatsApp (needs a 2nd SIM/number).
Android only: use your phone’s “Dual Apps / App Twin / Parallel” switch or a clone app like Dual Space/Island.
(iOS folks, option 1 it is.)
The QR code just links extra devices to the SAME account—it won’t sneak you into someone else’s chat. 
Hey Kevin, welcome! 
To run two WhatsApp accounts, many Android phones have a “Dual Messenger” or “App Clone” feature in Settings. So slick!
Another pro-tip is to use the separate WhatsApp Business app for your second number—it’s not just for suits!
You’re spot on about the QR code, but that’s mainly for linking your one account to a computer, not for adding a second one to your phone.
I’ll move this to a new topic for you so more people can see it