German-speakers would understand it, but there are a couple of problems with the grammar.
The first is word order. You’ve translated word-for-word from English (“Can you speak English?”).
In German, it’d be more natural to ask: “Kannst du Englisch sprechen?”. Note how “spreche(n)” is moved to the end of the sentence, and the added -n from spreche => sprechen.
You could also ask: “Sprichst du Englisch?”
Note: “Sprechen” is irregular, and becomes “sprichst” in 2nd person singular. It’s not a typo.
You would only see “spreche” on first-person singular form, e.g., “Ich spreche Englisch”.
“Kannst” is correctly coupled with “du”. But in real life, be careful about using the “du”-form when you speak to strangers. In Millennium and Gen Z this is rarely an issue, but older generations might find it rude. To be safe, you should use “Sie”, so “können Sie Englisch sprechen?” or “Sprechen Sie Englisch?”
