She looks pregnant. Feed a few times daily but very small amounts. If she doesn’t give birth right away it doesn’t mean she won’t give birth. If she gets stressed out she can absorb the babies. But not a huge deal because there will be more on their way. Female Guppies can hold sperm for 3 months at a time.
If you want to keep the babies make sure you have some foliage, heavy plants in there so they can hide. When she gives birth it takes a lot out of her. And it is not uncommon for her to turn around and slurp up the babies to regain her energy. So once again if you feed numerous small portions that will aid in the baby slurping. But be warned, once they start, it’s hard to stop them. You will have lots in a few months.