how can we make games for console such as ps4 , xbox one please tell me
In order to make games on consoles you need to get developer licence first to gain access to SDKs, which usually have lot of requirements you need to meet first. Go to those sites and read up what you need to do:
https://www.xbox.com/en-US/developers/id
https://developer.nintendo.com/
Once you registered developer in one of those, you got to this site to request access to console version of UE4:
The process usually requires some investment so it is best and safer to start deweloping game on PC first and then if you have something good consider doing ports on consoles.
To makes console porting process smooth make sure you game runs well with game controllers on PC