New to Fibre Phone/Internet: Installation & Wiring questions

Don’t confuse the installation info drafted for single family dwellings with what will happen in a multi-family dwelling. Here are my best guess answers to your questions:

• Telus runs Optical cable from the CO to the "last mile", and then to your home.  But where on (or in) your home does the Telus Fibre Optical cable terminate and what is that called (Demarcation box? )?

Usually this occurs at a telecommunications cabinet, or near your electrical panel, where existing ethernet or phone wiring exists. In some instances it is run to the location of your router.

• Does the Telus Fibre connect to an active "Fibre-to-Copper" conversion box?  What is the general term for this box, and what is the 2021 current brand / model that they use (so I can look up its datasheet 😄 )? 
  
  Telus uses a number of options, including a Nokia branded Optical Network Translator (ONT), or directly to the router.
  I assume this conversion box connects up to the existing (twisted pair) copper wiring you have in your house (so no need to run Cat 5e or 6, copper Ethernet cables, or different then RJ11 copper phone cables), so that you can use all your current phone and router electronics.  Is this a wrong assumption, and if so what does the conversion box output? 
  The ONT has ethernet outputs for data, and 4 wire for telephone. You will need ethernet cable between the ONT if installed, and the router. You will also need ethernet for your own networking. The phone output will be connected to your current phone wiring; it will not transmit data.
• In a multi-level house / townhome, will Telus run the Fibre cable to the mid-level of the house even if the current copper house wiring terminates on the ground floor / basement?  Now that I write this maybe that isn't the best idea, but the thought of having an active "fibre to copper" conversion electronic device in my unfinished parking garage, on the ground floor, rarely monitored, seems like a bad idea (heat/fire safety for example, or just dust, car soot, and bugs damaging it).

I don’t think you need worry much about dust, bugs, soot. The installer will discuss / determine the best option for your install upon arrival.

• What would be the recommended way to "hook up" Telus PureFibre to a 3 level Townhome, where the 1st level is just a ground floor garage?  Personally I would like to see all active electronics on the 2nd level, somewhere above the garage.

See previous comment.