I'm creating a Science Fair mobile security prototype which involves having the ability to remotely control my RPi 3 B+ with my android device while streaming live video from a NoIR camera. Being relatively inexperienced with Linux, I originally sought Wi-Fi access to be easier. However, I've extended my requirements to include a long-distance method of accessing my raspberry pi via 4G LTE (For example, accessing my RPi located at home while I'm somewhere else farther away).
What's the general process of doing this? Would I have to use a 4G LTE USB modem connected to my RPi while my mobile device is on cellular? Are there any major hurdles I would have to overcome concerning this plan? Is this even possible?