Outdoor lighting from hardwire to plug?

[Gunnermooch]

No electrical knowledge, I can change a plug and a light bulb but that's about it. My dilemma is this. I'm wanting to fit a 120w outdoor light with sensor for my parents who recently moved into a bungalow. To keep the cost down I'm wanting to know if I can just put a plug on the unit as all the ones listed at B and Q say they are "Hardwired" ?

Done a little research and the only information I can find is that an electrical item under 700w needs a 3 amp fuse?

If anyone has a quick guide or a link that will help I would be very grateful!

Thanks