What parts are suitable replacements for an Ender 3 Pro? I'm new to 3D printing and I recently got my first 3D printer, an Ender 3 Pro by Creality.

I've tried to find information about the type of nozzles should I look for. I'm trying to find stainless steel nozzles but there are so many models (M7, M8, etc.) and I have no idea what nozzle type I should get.

I've tried searching on Google but the only info I could find is that the extruder is an MK-10.

I am also looking for a heating cartridge for the hot end, but I still cannot find no information about the size that I need (15 mm/20 mm/30 mm). Also looked for info about the heated bed so I know what kind of thermistor I need (I found two types and no clue which one to get).

Where can I find some technical information about these?
The Ender 3 takes an M6 thread (metric 6&nbsp;mm diameter). Measurement of stock nozzle shown. 

Most sellers will list compatible printers Ender 2, Ender 3, Ender 4, CR-10, CR-10S, CR-10 Mini, CR-10-S4, CR-10-S5, CR-8, CR-7. Will Also Fit Any Other MK10 Heater Blocks. 

I recently bought some titanium alloy nozzles as the brass one got closed over after crashing into the glass bed.