yes, your plant needs blue (6500K) to veg to its fullest potential , and red (2700K) to veg to its fullest. having a broad spectrum wont hurt anything. maybe just wasting light that could be the right spectrum for its life cycle.
You can mix them I have done it. That being said you can Monkey can fly if you throw them out of plane. Atleast till they hit the ground. You 6500k or blue lite should be used for Veg. This color lite is best for that time. The 2700k or red orange is best for flowering. Its simple you can use both at the same time but your going to wasting power on lites that you could get better results using all the same color.
You dont flower with HPS and MH the same as you dont veg with both there is reason.