Shimano 11 speed road and mtb are basically not compatible.
However there are a few solutions in terms of running a 11-36 cassette:
a) there is a video on YouTube that shows a 105 rear mech with the b-screw turned the other way running a 36t no problem
b) there is also a hack where you can switch out the cage of a 105 rear mech for some (LX Trekking 9sp I think) other cage and it’ll play nicely with big cogs
c) The Lindarets Roadlink will fit to the mech to allow this to work as well
In terms of cassettes, SRAM do a road 11-36t one in 11 speed that will fit a new 11 speed hub. The MTB Shimano 11 speed cassettes will fit a road 11 free hub but you’ll need to add a spacer (that should come with the hub anyway) as it’s basically the same width as a normal 10sp mtb/road cassette.
Does that help?