Battery is dead, That is why the fast clicking from the starter selenoid. (It doesn’t have the power to hold down the internal spring). Put in a new CHARGED battery & it should start. When running, Put a DC volt meter on the battery terminals. It should be reading 14 ~ 14.5 volts DC when revd up (Charging the battery). If you can’t get 14 plus volts, The bike isn’t charging & the bike will quit when battery runs low enough. As for charging problem, Usually the voltage regulator or stator.