If you lost your remote, I guess you can try using a bluetooth mouse or just download android TV remote app in playstore.
Sadly I have no idea. Some thoughts: borrowing a remote from someone you know, purchasing one from Mecool (may not be compatible) or buying a new Mi tv stick, use the remote for what you need and then sell it.
Need help out here
The Mi Tv stick has a micro usb port. Can you get a micro usb to usb otg cable? Then plug in a mouse to navigate the screen with the cursor?
EDIT: nm, it uses the micro usb as power.
Mi TV stick has no "wifi button".