Ordering politely: Ich hätte gern …
At counters and in cafés you’ll constantly hear Ich hätte gern … (I’d like …) — an extra-polite cousin of Ich möchte. It’s a fixed chunk: hätte, not habe.
Learn it as one unbreakable chunk — and möchte always works just as well.
Tip
hätte gern and möchte mean the same thing at the counter — möchte is all you need to say.