Two step can be, "Execute on Press or Release".
It can be execute on release only, and spam it at the pace you choose.... press 1 = Step 1, press 2 = Step 2.

You could physically have two mapped keys.
"1" is mapped to keybind A, on step 1.
And another mapped key, with a hotkey of "2" sends whatever also on Step 1.
And then alternate 1's and 2's, as the keys you spam.

The method doesn't really matter.
Although going two steps on one mapped key will let you mash a single button for DPS which is easier.