Here are some examples:
* "I have a plan to visit my family." (Here, "plan" refers to the idea or scheme)
* "The architect presented their plans for the new building." (Here, "plans" refers to the drawings or blueprints)
However, "plan" can also be a verb:
* "We plan to leave early tomorrow." (Here, "plan" refers to the action of making a scheme)
The context will determine whether "plan" is used as a noun or a verb.