I don't know EXACTLY what is your hp 360 envy m6 but I know for sure it does not have docking port therefore you have to use USB docks. Very hard to say which one since I have no idea what is your requirement. Anyway, if you wish to connect more than 1 external monitor you need a DisplayLink Certified USB dock.
Please enter your requirement on the following link and it will find for you few options on market today including some HP products:
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