For green building design how much percentage we can reduce in the following parameter: energy use, CO2 emissions, water use, and solid wast?

For LEED Projects, there are pre-requisites that the building has to achieve a minimum percentage of reduction from a baseline for both water use and energy use. For example for water the baseline is to reduce water use for atleast% and then the more higher percentage of water use reduction you achieve the more points you get like you reduced% you get a point extra,% to points extra upto a maximum number of points. In case of energy it is the same, the building has to achieve a minimum energy use reduction percentage from a baseline and then the more energy you save the more points you get. For CO2 emissions LEED version4 has introduced carbon offsets to mitigate Scope1 or Scope2 emissions on a metric tonne of carbon dioxide and earn LEED points. For solid waste, LEED awards points for Construction Waste diversion from landfills and incinerators. 

I hope this brief answer helps!