Generally, you want a capacitor that matches existing one. The sticker (circled below) on the controller makes me think yours is a 4.5 uf capacitor.
Those 2 black boxes are likely your existing capacitors. The one with 3 wires is usually the one that controls the fan speed (you wont need this one because the Inovelli canopy module has its own). The one with 2 wires is usually the motor start capacitor (which you will need or the fan will not start or may spin in the wrong direction).
If the capacitor in the photo with only 2 wires says 4.5 uf, that would be my guess as the correct one.
