What do I do if on my W-2 where it gets to box 12.. mine has 12a code, 12b Code,

and 12c code, but they are all blank?? But turbo tax app ask me to make a selection and it has all kind of choices and I don't know what to put or if I'm supposed to leave it blank, since it's all bla

Business & farm

Leave them blank.  Only enter box 12 if there is an amount listed.

Business & farm

Don't overthink it ... if the form has blank boxes then in the program you will also leave the boxes blank.