Multifamily Zoning Home convert to a duplex

[Sam Park]

Hi, I am currently located in Fair Lawn, NJ.

My home is considered a Multifamily Zoning. We are a single family home, and I want to renovate my home, and turn it into a duplex. (First Project) 
Considering this is a multifamily zoning, can I just simply convert it into a duplex?  

What are the regulations regarding the size of the renovation to the home?

Am I allowed to convert the lawn I have into another parking lot for the second family?

Am I allowed to remove the tree in front? 

Can I shrink my backyard for essentially a bigger home (extended to the back)? 

Are there anything I need to look out for?