stevietee10's information is very good.
Personally, if using the Battery Eliminator Circuits [BECs], I'd only use one of the four. If I need more current, I'd drop the BEC's in the Electronic Speed Controllers [ESCs] and use a separate, dedicated BEC (sometimes called a UBEC).
A quick question in reference to "iam not so familiar with EScs and knows nothing about battery eliminator circuits etc"
Rhetorical but, why did you purchase these particular units?
i.e. why with BEC, Why this current, and (as not shown) is the operating voltage range correct? (usually stated in "S" e.g. 3S to 4S)
I only ask, as I spent about 3 months spec'ing all the parts for my first quad a few years ago (much more info available today). I have a very good grounding in electronics, but brushless motors and propeller designs/efficiencies were new to me, and so I took a long time going around and around the design process. Being a tight-wad, I was also trying to use a minimal budget.
Best of luck with your build! Don't be put off by failure. Do have fun, and fly responsibly. Check everything over and over! Buy lots of cheap propellers (and a balancer) before lashing out on expensive ones.
The air is an hostile environment in the case of a failure, this is why aircraft have flight checks on EVERY flight! Gravity is an unforgiving mistress!