I am going to guess you can not.
To use any device as a range extender...ie wifi repeater..it must have a special feature that supports that. It is not a common feature on a hotspot or common routers. It most times is a specialized device.
Now if you can run a ethernet cable and the device has a ethernet port you can likely use it as a AP. Most those things called "MIFI" tend to look like a cell phone and have no ports. Still for most people unless they have ethernet cables in their walls running any device as a AP is not a valid option.