These coins are indeed quite difficult to understand: first you have to look at the obverse: the legends can be BELGIE BELGIQUE (Dutch legends first= KM#117) or BELGIQUE BELGIE (French legends first = KM#116)
You have KM#117, Dutch legends first.
Then you look at the edge: it is a milled edge with the same words BELGIE BELGIQUE as edge lettering. These words are separated by a crown (=KM#117.1) or a star (=KM#117.2). Most chance your coin is KM#117.2, with a star separating the edge lettering BELGIE BELGIQUE.
There is also the positions: the definition is as follows:
when you put the coin on a table with the denomination (in this case the lion with 5FR) visible, look at the edge lettering. If it is upright, your coin has position A. If it's upside down, your coin has position B.