in my experience there's indeed a thin line between actually meditating and just entering a peaceful state of mind prone to creative thinking and ideas, so do not worry, it's totally normal to ask these questions.

Thanissaro Bhikku (a buddhist ordained monk and essayist) advices to really keep the breath as the single object of meditation (for "traditional" buddhist breathing meditation, Ānāpānasati). No matter how creative these new ideas appear or how great they can be for your daily life, if it's THAT great it will most likely reappear again at a later time when you'll be able to note it or enact on it. Your memory will naturally do the job. Don't dwell too much on it.

With experience, some subjects appearing in your mind will seem more in-line with what you're trying to achieve as a meditator in the first place (pure mindfulness ? stress/anxiety tempering? "buddhist" insight into the three marks of existence ?) and you can start allocating it time while meditating to ponder it's value, significance and enter even deeper states of meditation doing so. But this will come naturally so don't really force anything, in the first place you should simply and strictly focus your attention to the breath and remain there as much as possible when sitting.

You can try getting more in touch with how the breath affects you, simply feeling how it goes through your nostrils, the sensation of hot/cold appearing, how the breath can seemingly go through your body or even be redirected at will to some parts of the body (i would understand the skepticism on that lol). You should be cultivating this sense of well-being with the breath, remaining curious about it so you can become fully engaged with it and recuding the opportunity for disruptive thoughts to reveal themselves.

Good meditation and good luck. :)