There are three ways to do nominalization. Today you will learn one of them. Korean uses verb as a noun a lot, so you need to know how to change from verb to noun in Korean. When they change from verb to noun, they add 기 to make noun; it is one of the ways to make noun. I will give you some examples how to change it. Please see examples below.

To read –읽다 > reading 읽기

She reads a book/그녀가 책을 읽다. V

She like to read a book/ 그녀가 책 읽기를 좋아한다. N

To eat – 먹다 > eating 먹기

He eats fruit/ 그가 과일을 먹다. V

He like to eat fruit/ 그가 과일 먹기를 좋아한다. N

Korean uses 기 with other form and meaning. For instance, V+기 전에 (Before doing something) > 책을 읽기 전에, 과일을 먹기 전에. V+기 때문에 (Because someone does something) > 책을 읽기 때문에, 과일을 먹기 때문에.

As you may know, learning Korean is super hard; it is one of hardest languages in the world. So, Please don’t get stress out too much and just study one by one.