What are the holidays for people who work in Germany?

I was wondering, is there a summer break in Germany just like in Spain? Other than that, how can I find out if there are weeks off for workers, I can only find info about school breaks but I'm interested in the usual holidays for people who work, specifically weeks off (like the easter week).

Other than the time between Christmas and New Year, there is no period when German companies are usually closed.
All employees can take their (generous) annual leave entitlement at any time throughout the year. Of course, those people with kids will do so during school holidays (which you already found - they differ from state to state!), so you can expect the office to be quieter and any progress slower during such times.