Where does the fertilization takes place?

In humans fertilization occurs in the end of the fallopian tube away from the uterus (close to the ovary). The egg and the associated cumulus cells are ovulated (released) from an ovarian follicle and picked up by the fallopian tube. The tube pulls it inside where the sperm can find it.

Keeping this in view, what happens during fertilization where does it usually take place?

A pregnancy starts with fertilization, when a woman's egg joins with a man's sperm. Fertilization usually takes place in a fallopian tube that links an ovary to the uterus. If the fertilized egg successfully travels down the fallopian tube and implants in the uterus, an embryo starts growing.

How does conception happen?

After the egg is released, it moves into the fallopian tube. It stays there for about 24 hours, waiting for a single sperm to fertilize it. All this happens, on average, about 2 weeks after your last period. If no sperm is around to fertilize the egg, it moves through the uterus and disintegrates.