Infinitives are when you use the preposition 'to' with a verb. In this sentence, we do not have the word 'to', but it can be inferred. In other words, if we were to add it (to add - an infinitive), it would make sense. So, find the main verb. In this case, it is helped. What did the counselor do? It helped. Helped whom? Me (indirect object). Helped me to do what? 'to' learn. Therefore, the hidden infinitive is 'learn'.