This is a view of the female anatomy of a flower called the carpel. And this part right here is the part that sticks out and capture the pollen seeds.
this is male reproductive anatomy of a flower, known as the stamen. and it's similar to a male reproductive system because it also have a part called anther and this contain the plant's male gametes and it's also where the pollen seeds get release.
this image is the anthers all over the stigma, the anthers are like sperms and the stigma is like a female reproductive system.
this is a picture of a plant's ovary and this part contain the ovules.
Summary
Summary
So basically, how fertilization occurs in flowering plant species like Brassica oleracea works is by doing self pollination and it's mean the plant does the whole reproductive system on it's own and how it works is the plant have a part called carpel and it have a job of capturing pollen grains which contains sperm, and those pollen grains are coming from the stamen, the male part of the plant. After the pollen grains get captured on the stigma of the the carpel, it will get transferred down to the ovary where the plant contains the ovules that are immature and unfertilized seeds, and this part can be found under the carpel. So like that the pollen grains get to the unfertilized seeds and then turn create an embryo that has the potential to become a new flowering plant of the same species. And after that, those unfertilized seeds will become a new fruit.