What happened to obito Uchiha?

Answer 1

When his friend and crush Rin was captured by some enemies from the Rock Village, he went to save her, with a younger Kakashi. They found her in a cave and untied her after defeating a shinobi. While leaving, the shinobi did a rock breaker jutsu, causing a cave-in. Kakashi got hit and fell, and in an attempt to save him, Obito was crushed under a rock. Knowing he was going to die, he gave Kakashi his remaining Sharingan eye, since Kakashi had lost his eye in a battle just before.

Answer 2

kagami uchiha died before the massacre of the uchiha clan or during it..either way he was killed..although his body was never found there is a chance that he could be alive..no body knows for certain because kishi (the writer of naruto) never explained kagami's story in depth..kagami is believed to be dead or alive..you choose..maybe kishi will tell us one day