Is a latte a coffee?

If you're talking about a latte literally, then no. A coffee is black and generally stronger in flavor with less milk. However, if you're asking the question as an idiomatic expression, then yes it can be taken as a coffee. there's literally a world of nuance to explore here with "latte" sometimes equating with "coffee", and how strong or not strong that might be - which will depend on the strength of the espresso shot itself but also on the amount of milk included that kind of thing. so for this question, i'll say somewhat not obviously depending on context.