There's no boundary to meditation beside your own discipline. Don't think if you're meditating for too long or not enough. The baseline you set yourself should be according to your own mind.
If you're starting breath meditation to better your focus and awareness, you can measure progress by how long if takes your mind to become exhausted from the effort, or with how much ease it slips from focus.
In my experience, meditation progress is nowhere near a neat line of any kind. It's more like pic related. Some days will be great, some will be bad, but there's a slow and overall improvement. So don't be take to heart a sudden dip or rise in quality.
As for knowing about Buddhism, it depends what you mean. If you want to fully follow the teachings and 'convert' as it were, then yes, you should go and research the core principles and teachings at least. Buddhism is not like other religions, however. It shows you the way and asks you to walk it yourself. So; to achieve enlightenment is something only you can do for yourself, and no amount of knowing 'about' Buddhism will help you with that.
If you meant meditation and other mind-based practices, it depends.
Some meditations are meant to be spiritual, with specific goals and ways of thought. Others, such as breath meditation, are not dependent on faith at all, and are entirely personal as to your technique, method, goal, etc.
It never hurts to do your research, and the wisdom you hear from others may very well help you greatly, but with meditation it is your own mind fixing your own problems. You can see that this comes down to your own wisdom, and not that of others.
Hope this helps, Anon.