Can the orange star be planted in my garden, or should they be left in pots?
The botanical name for this plant is Ornithogalum (if it is the variety I think it is). This Orange star grows from a bulb and can be planted in the ground in zones as low as 3-5, depending on the variety you have.
I just bought a Orange Star or Star of Bethlehem- Can these be grown as an indoor plant?
You can, but it won't flower year round. I recommend this link: http://homeguides.sfgate.com/grow-star-bethlehem-plants-indoors-98546.html
My mother has allergy problems. Is the orange star flower a suitable plant?
I'm unable to answer your question, as I'm not qualified to determine if your Mother would be allergic to the pollen in this flower.
https://www.gardeningknowhow.com/ornamental/bulbs/orange-star/growing-orange-star-plants.htm
after blooming, how should I care for the bulbs?
This article will help: https://www.gardeningknowhow.com/ornamental/bulbs/orange-star/growing-orange-star-plants.htm
I want to collect the seeds from my plant. But I do not know exactly where they are located. A picture would be great.
Seeds are a part of the plants' sexual reproductive cycle. This means that a male stamen, bearing pollen, will need to pollinate the female stigma of the flower. Once the flower is pollinated, the ovary will swell beneath it. Once the pod has swelled and starts to discolor, then you can take the seeds from inside.
My plant already bloomed now what to do I do to care for it
Here's an article that will be helpful:
https://www.gardeningknowhow.com/ornamental/bulbs/orange-star/growing-orange-star-plants.htm
Read articles stating, PLANT OUTSIDE.? BUT ALSO: should be INDOOR house plant in indirect sun. So which is it?? IT GETS VERY HOT HERE AND HUMID IN SUMMER.. ALSO:..WHAT TYPE FERTILIZER FOR THIS PLANT. Thank You very much, My first time with this plant.
They will not survive the outdoors in your zone. They are only hardy down to zone 7, so you may need to grow them in container, or dig them up each year and bring them in.
If you grow them in container, and change the soil every year, then it will not be necessary to feed the plant. They are known to grow in soils with low fertility. If you choose not to change the soil, then a granular all purpose will be fine, once per year.
Here is an article for more information on the plant:
https://www.gardeningknowhow.com/ornamental/bulbs/orange-star/growing-orange-star-plants.htm