If I lived in California or Florida where I could have my chams outside for all or part of the year I would. I have a big collection of potted ones on my patio and throughout my garden. None of them would do well inside though.
bonsai is a style of gardening, not a type of tree. any species of tree can be grown or maybe bought as a bonsai tree. the most commonly sold "bonsai tree" is a juniper or some kind of pine that wont live indoors, but you can probably find a bonsai ficus or something that should work just fine indoors for your cham