Can anyone tell me what kind of visa it will be if i apply to attend mrcp convocation ceremony in edinburgh. The types of visa are confusing.
The first set of questions on the application would be filled out like this screen shot...
For the generic case, that's really all there is to it.
You have a previous refusal where they got you on funds parking. Hopefully you are in a position to make a better presentation to the decision-maker. There are some reasonably priced advisers at The Association of Regulated Immigration Advisers and for heavy lifting (which I recommend in your case) your can check out the Immigration Law Practitioners Association. And the main point of reference for finding a solicitor is the UK Law Society.
I would also recommend that you make a careful read of Should I submit bank statements when applying for a UK Visa? What do they say about me? before assembling your evidence. There's more background reading at proof-provenance-of-funds.
Note: disclosing that I am a long-term, contributing member in good standing at those resources I linked to.