I have recently started a mphil, with promise that it will be converted to a Phd.

I did not have an official interview when I joined this lab, so I did not know the position well. Basically my previous lab sent me here. The problem I have is that my supervisor is a really kind person, but totally no thoughts. He is a physician and I agree that he is a good doctor. However he has no ideas for my research project- and I have suggested a few but he refused, saying he had done similar stuff(but i looked up and its totally different). The current research he is asking me to do is like using moisturiser frequently will improve skin hydration.

I cannot discuss any science with him and I dont think he is capable to supervise a sensible phd project. Should I finish my mphil(2 years) and go somewhere else for phd? Or should I not waste time and find another placement? May I have advise on how to identify a good supervisor?

I'd probably say look for a another PhD elsewhere. It's going to be really difficult without a supportive and knowledgeable supervisor. But find a PhD first before you jump ship! And bear in mind it's really difficult to find out how good a supervisor is unless you meet ppl from their lab and ask them, and obviously that's hard to do.

It's probably also worth suggesting that it should not be taken for granted that their is a 'promise that it will be converted to a Phd.' You have to work towards it and then upgrade if succesful. So I'm not sure you would be able to do the two separately.