Easy to add a virtual device in HE - just go to the devices page and click on "Add Device" then "Virtual" (rightmost button), then give it name and choose "Virtual Switch" for the "Type".
Once it's created you can go into the HE Alexa Skill App (not the skill on Amazon!) and add it under "Select Devices". It should then show up in Alexa.. From there in Alexa you can create routines that sync the virtual switch with the bulb - when switch turns on, bulb turns on etc.
The video doorbell stuff is a little tricky.. For example the Ring Doorbell is nice and there is a community Ring Integration for it but not sure how well it works..
Once you get comfortable there are a bunch of things you can do to extend your setup depending on how technical you want to get.. mostly it involves running secondary servers for extra functionality - like HomeBridge.io etc.