Well i work at a fast food restaurant and i stole an ice cream and i was written up a violation notice

i was already thinking about quitting before this incident happened but now i really want to quit because I've realized i really don't like working there and the people are just bleh to the max. well in terms of applying for a new job, up until now I have had a good relationship with the manager that actually employed me and a different manager wrote me up. The manager that actually wrote me up seriously hates me. So should i use my old employer as a reference? I am sooo confused I've never been written up before i don't know what to do. is what i did minor or major?will it be on my record?