Hmmm, CNC requires full cash and you get no leverage. Also, you can only buy first and then sell. If you want to take leveraged trades and also want to take a short position first, then you should use intraday product type MIS. But if you only want to buy and then sell either on the same day or coming days, then CNC is good.
If you are certain of an upmove, then you can buy more shares for the same amount using MIS for intraday, and then convert as much of this as you want to CNC if you want to take it to the next day.
No, you cannot carry leveraged trades in equity. You can only carry CNC trades which require full cash. MIS positions which are open will be auto squared off at 3.20pm.