I have a question i need an answer to...How is Canada's involvement with the US (in Afghanistan) similar to Canada's involvement with the British during WWI (in terms of motivation)? How is it different? Im doing a project for university and i am having troubles with this topic

i think you would be better off looking at the differences rather than similarities.
resemblances between the two are pretty thin on the ground.  in ww1 there was a great deal of popular support for bashing the boche a good one while now public opinion is rather more dubious about the wisdom of sending troops into 'stan.  in ww1 for instance the municipality (county equivalent) i grew up in lost every man between 18 and 25 killed in the war other than a few medically incapable of joining up.  today the average canadian doesn't even know a person serving in the military.

 

the guys that are in 'stan are there to help develop the country in hopes that if afghan peoples' lives get better they'll be less likely to welcome the taliban back.  it's one of those grinding nasty little things that will likely go on for a decade or two that will produce a steady flow of coffins coming home.  canadians have gone a long time without something like that going on and it's not sitting well with the civilians.  i do not know if our leadership will stick with the program long enough for it to have a chance of it working. 

 

i wish you luck with your project.