How to set up the capacity in the resources

Dear,

I'm setting up the capacity in the resources so that we can do some schedule. But after reading the info from the technet as the below snapshot, I'm confused. If the AX will consider the work hour according to the calender, how we display the real work time. For example, in we have 5 people in this workshop(resource), they work 8 hours every day, so for this resource, we have 40 hours(5*8) every day, this is our capacity but in the calender, it can't display this info. So, could you help me make sense? Thanks.