Yes, in short but only for periods of a few days, especially in winter as this will break dormancy. Never place hardy types never near a heat source.

Most hardy conifers and hardy shrub or tree species used are fine for a week in summer, but not for much longer. They need plenty of light but not in hot sun.

NO you cannot KEEP any bonsai indoors. You can DISPLAY any bonsai indoors for a few days only.
If the tree is a tropical or semi-tropical species then it IS an indoor bonsai.

Yes, the Ficus family and some others. Look them up on line.