Richard May married Jane Edwards in Redruth, Cornwall on 13 March 1823. Marriage records at that time don't usually show the parents' names but only show if the groom/bride were 'of this parish' or not. Even if they were resident in the parish at the time of the marriage (and at least one of them must have been) it doesn't mean they were baptised there.
there is a baptism of Richard May in Redruth on 13 July 1794, which might be him - parents Richard and Jane May. But it's impossible to be certain - there are a lot of other baptisms of Richard May in Cornwall between 1790 and 1805 and any of them could be the one you are looking for.
Jane Edwards even more difficult to pin down - Edwards was and is a very common surname. There is a baptism of Jane Edwards in Madron, Cornwall on 24 June 1792, father John (mother not mentioned in the index so you would need to look at the film) - but again, impossible to be certain that this is the right one.