I want to put in a catch can for my 2011 ranger 4.0l
I can't find any kits for it, could anyone help? please?

 

Not sure why you want one but you can use any off the shelf kit that uses the same or slightly larger diameter hose.

Catch can attaches to the PCV Valve hose so that is the size you want to match.

Unless you have very high miles, 250k+ or you know you have some bad rings, a catch can really isn't needed.

Oil vapor in the crank case and valve cover comes from Blow-by.
When a cylinder fires, very hot expanding gases form and that pushes the piston down to give you power, but some of those very hot expanding gases will push passed the piston rings and into the crankcase, this is called blow-by, all piston engines have blow-by, gas or diesel, even steam, lol, new engines have blow-by and as the rings get older blow-by increases.
As these very hot gases travel passed the rings they vaporize some of the oil on the cylinder walls, this is the source of the oil vapor in the crankcase and valve covers.

Oil lubing the bearings and valve train is squirted out, NOT vaporized, this oil just settles out on surfaces very fast, so is not pulled into the PCV Valve hose.

The Catch can is only used on high miler engines to prevent oil fouling of spark plugs from excessive blow-by.
Any other reason is just someone trying to sell you something you don't need.
Leaking valve guide seals or oil leaks are not effected by catch can use, and if not installed correctly it can make these worse.