I assume you are referring to human females. A female releases only 1 egg per cycle of 28 days or so.
The female body over its lifetime develops a certain number of eggs. These are released one at a time during the mensturation cycle, every 28 days or so. In all, a healthy female body will release these eggs over a period of 30 or so years. In exceptional cases, 2 eggs may be released at one cycle, that is how twins are born.
During each cycle, one egg is released from the ovaries. It waits in the Fallopian tubes for fertilization by a sperm. If it is not fertilized, it is removed along with menstrual fluids.
Just a fun fact, unlike men who can produce sperm everyday, females are born with all the eggs (follicles) they will ever release.