I'm new to Canvas instructor. I was trying to connect to an LTI 1.3 provider through the Free-for-Teachers account. I received the following:
As far as I'm aware it's not possible to add a LTI 1.3 tool to the Free-For-Teachers provision from Instructure. You can only add LTI 1.1 tools.
LTI 1.3 tools need to be added by Instructure to the instance and only then they can be installed in a course.