I grow several other ficus species for bonsai. I just play around with it am not a serious bonsai artist, just a duffer. They have naturally smaller leaves and fruit although the fruit is not edible. We have a member here who has written a book on ficus bonsai. Jerry is his first name forgot the last. Hope he will chime in. Fiucs carica is a pretty hard subject for bonsai and is usually attempted on a larger scale. And as Bass had commented, you will be pruning off most of the fruiting branches, so if you decide to try bonsai don't expect much fruit from that tree. Afigfan mentioned above that a common technique is to take an established tree and cut it back severely,then work with the newly sprouted branches. That will give you the thick base in a hurry. It's a challenge but is doable I lost a nice one in winter a couple years back when I let it dry out too much.