Ok, So I am having a hard time finding on the PHB section (page 178) anything about learning spells from another class.

Now the situation is this.

My bard friend wrote a scroll for me of the spell cure light wounds. He casts it as an arcane caster not a cleric. I understand that my wizard should not be able to write to his spellbook any cleric spell from a scroll because those are divine magic. But what about the specific case of the Bard since it is arcane?

What about another strictly arcane spell he wants to teach me in the future? The spell Heroism is a level 2 Bard spell but a level 3 Wizard. If he scribes the scroll for me do I learn it as a 2nd level spell or I can't learn it at all?