In the design phase there are the option of relative or absolute size
I want to customise the same settings using blocks, however, how do I know which properties these are? For example the 100 and 20 here, are these ,relative or absolute, px or %?
It seems like margin and padding cannot be customised in blocks
Yes, but it has to be “relative” to something else. In my example above I outlined how to set the width of a component to 25%, relative to the width of the Screen. i.e Screen width / 4