Most species of treesin these kits are of species that are supposed to be outdoors. So chack what you have, but work towards making a place outside to grow these plants.
For bonsai, plants that could be kept indoors are less than ideal. In order to grow bonsai you will need to get perfectly healthy plants, or else all you do to them will risk their life.
If you really want to grow from seed, be aware it takes a long time. Also, stop buying these kits. They are a pricey rip off. There are no bonsai seeds. There are only seeds of plants, some species of which are more suited for bonsai.
If you are in a temperate region, consider getting seeds of trident maple or larch seeds. These are fairly fast growing species and will yield you acceptable results in a reasonable amount of time. e.g.,
www.bonsaiempire.com/forum/general/8325-...-years-in-the-making
Do let us know which species you are growing. Many people on this forum dabble into growing plants from seeds and have the expertise to get you going. If you are headed into winter, I would wait a bit. Many temperate species need a winter period of minimum 90 days to break them for germination. However you ideally want them to germinate in early spring. So planting them in december, january and keeping the pots outside (Shielded from rodents and birds) would be a good start.
Do look into stratification though
www.growingbonsai.net/germinating-treeseeds/ 
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