Learn Hardcore Korean: gongwoni johayo.

Korean often omits pronouns (like I, you, etc.) when the context makes them clear. In 공원이 좋아요, the speaker’s perspective (“I”) is understood, so you don’t need to say 저는 or 제가 unless you want to add emphasis or clarity:
• 저는 공원이 좋아요 – “As for me, I like the park.”

What does 좋아요 mean here and what form is it?

좋아요 is the polite-present form of the adjective 좋다, meaning “to be good.” When you say Noun + 좋아요, you’re literally saying “Noun is good,” but in English it translates as “I like Noun.”

Why is 공원 marked with 이/가 and not 을/를?

In Korean, when you evaluate something with 좋다, the thing you like becomes the subject, not the object. Subjects take 이/가. So:
• 공원이 좋다 = “The park is good/I like the park.”
If you used 을/를, you’d be treating 공원 as an object, which doesn’t match how 좋다 works.

Can I say 공원 좋아요 without the particle 이/가?