Jose wrote

Usually (in the US) one gets a pilot certificate for single engine
I was told that the C336/7 was created so that a person with a single
engine rating could fly a twin engine airplane (since there would be
no critical engine, and no adverse yaw, and no blueline). However,
the FAA decided that not only did you have to have a multi-engine
rating =and= a type rating for that particular aircraft.

An Aircraft Type Rating is required only if the C-336/337 weighs
over 12,500 pounds.....not very likely.
Now...the possibility exists that you have written a very poorly
composed paragraph.

Bob Moore