How do I know this is anchored frame, text frame or other.
You have already selected the object in question. Now use Graphic > Object Properties. This lists the type of object in ther dialog title.
Klaus is correct—and I marked his answer as correct—but that's template frame. It has a flow tag assigned (Flow A) and auto-connect is enabled so text flows from one page to the text automatically.
An anchored frame is added when you import a graphic with your cursor in the text and is attached to an anchor symbol (an upside down T).
Got it, thank you Barb!