IF you live with your parents and are growing, they should really know about it. It's only fair to them. If you can't tell them about it, you should be growing outdoors on public or utilities land.
Shwag seeds are good practice for newbs. You can get perfectly acceptable results with proper care. But if you're buying cheap shit with lots of seeds in it, there's a good chance it's an outdoor sativa strain and will turn into a monster.
Seriously get permission from your parents and do it right.