Translation:You should eat
No, the verb stem is 'kula'. 'Ukule' = 'ule' just like 'ukuje' = 'uje' (verb stem is 'kuja'). Alternatively if you're telling someone to eat, the imperative form would just be 'kula' which is the command 'eat'.
-ji- is what indicates someone is performing an action on themselves. To use your example, 'you should eat you/yourself' would be 'ujikule/ujile'. It's common to use '-la' in place of '-kula'