Hi Donna. Most commercial tangerine and other citrus trees are grafted trees onto hardy root systems. That means they take the tree part of a delicious fruit and cut it off and grow it on to a root that is disease and insect resistant and grows strong.
When the fruit blooms insects usually pollinate it for
seed production and the fruit is just fine. But if insects pollinate with a different type of fruit tree the
seeds inside the fruit may be a cross breed between your lovely tangerines and some other citrus. This can make for some interesting fruit grown from those
seeds, sometimes very good and other times not so.
Now all of that being said, you can try
growing your own from the
seeds you have. Make sure they are dry. Plant in soil and keep evenly moist. A glass of water is not recommended.
You do not need to feed
seeds. They come with all of the nutrition they need to begin their life. After it gets for or so sets of true leaves then you can feed lightly.