Would that be correct to say, 'I want my idea to mature' or 'I want my idea to grow up'?
In certain contexts ideas can certainly "mature" or "grow", but not normally "grow up"… although they can "grow out of": "This idea for a business grew out of a discussion I had with my father". They can also "evolve", "develop" and "progress".
not a teacher
Student or Learner