Sure. Why not? Unless you already weight over 100kgs yourself, that should be plenty of weight for most exercises.
If this is a home gym, you might eventually want to find a bit more weight for your squats and deadlifts, but 100kgs should be a good start.
It's not how much weight you have to work with as it is how hard you are willing to work. Besides, a big part of "an athletic looking muscular physique" comes from a proper diet and plenty of exercise.