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Is there an ending symbol to put after the text or does the quotation end with a return key press?

No. Just type it this way ➟ >This is quoted text. This is quoted text.

and it will appear like below.

This is quoted text. This is quoted text. This is quoted text. This is quoted text. This is quoted text. This is quoted text.

Yep, it's good practice for sure. & I might actually link this FAQ in the comment.