Attaching the -는 것 or -는 거 ending to the verb stem is the most common way to transform a verb into a noun.
먹다 (to eat) -> 먹는 것 ~ eating, the act of eating
케이크 먹는 것을 좋아해요 ~ I like eating cake
마시다 (to drink) -> 마시는 것 ~ drinking, the act of drinking.
가다 (to go) -> 가는 것 ~ going, the act of going
In the above I have written -는 것, as this is the form it takes in writing.
When pronouncing the examples, however, the final ㅅ mostly disappears => -는 거 (unless it is followed by a particle such as 은 or 을 like above which would bring out the ㅅ sound).
Written language: -는 것
Spoken language: -는 거