What’s the different between “steak and “sear” when you are cooking？ For example, “Sear the meat first to retain its juices”. Can I just exchange “steak” instead of “sear” in the sentence above？

No. Steak is the meat. Sear is a cooking method. They are not the same word.

No. A steak is a cut of meat, searing is a method of cooking. https://dictionary.cambridge.org/dictionary/english/steak https://dictionary.cambridge.org/dictionary/english/sear

They're not the same thing at all. "Steak" is not a verb; it is a type of food (a thick slice of meat, usually beef).

A steak is a cut of meat. Sear is a way of cooking. Go and double check the definitions for these two words-- they are completely different and not interchangeable.

Steak is a cut of meat, it's a particular piece of beef. Sear is a method of heating something, but only on the outside. The inside remains cool. You can sear a steak, (heat it quickly so the outsides cook but the inside does not). You can not steak a sear, (this is a nonsense sentence).

Sear means to cook at high heat on the outside so the liquids don't come out. Steak means to cook like steak, and is less precise. I have never seen steak as a verb until now, and I like cooking - I wouldn't say it is a particularly common usage.