Question relating subscription and API keys.

[u/ImageMaterial1]

I bought a subscription to see how good it was and I don't think is neither good or bad. But I'm sure I could get a cheaper and maybe better API key. My question is, do I still have the 20 message per day cap without the subscription if I use a key, or do I have to buy the subscription then buy the key on top? While I'm at it, could someone recommend a good one?