Learn Hardcore Korean: keompyuteo hwamyeoneseo yeonghwareul bwayo.

컴퓨터 means “computer,” 화면 means “screen,” and -에서 marks the location where an action occurs. So 컴퓨터 화면에서 means “on (the) computer screen.” If you used -에, it would simply indicate a location of existence (“at/on the screen”) rather than the place where you actively watch something.

Why is 영화를 marked with -를 instead of -가?

-를/을 is the direct-object particle in Korean. It tells you that 영화 (“movie”) is what’s being watched. The subject particle -가/이 would mark the subject, not the object, so -를 is correct here.

What is 봐요, and how is it formed?

봐요 is the present-tense polite form of the verb 보다 (“to see/watch”). The stem 보- combines with the polite ending -아요, but because 보다 ends in ㅗ, 보 + 아요 contracts to 봐요.

Why is the subject (“I” or “we”) omitted in this sentence?

Korean often drops the subject if it’s clear from context. Since the speaker is presumably talking about themselves (“I watch a movie…”), you don’t need to say 저는 or 우리는—it’s understood.