Learn Hardcore Korean: naeil dongari moimeseo sayonghal kamerareul hwaginhaesseo. - I checked the camera I’ll use at tomorrow’s club meeting.

확인했어요: polite but still conversational (you’d use this with strangers or in everyday polite settings).
확인했습니다: formal and often used in presentations, reports, or with superiors. All mean “I checked,” but the level of respect or formality changes.

동아리 모임에서 literally means “at the club meeting.” The particle 에서 marks the location where an action happens. If you used 에, it would imply direction (“to the meeting”) rather than “at” or “during” the meeting.

What does 사용할 카메라 mean, and why is 사용할 placed before 카메라?

사용할 카메라 means “the camera that (we/I) will use.” In Korean, relative clauses always precede the noun they modify. Here, the verb 사용하다 is converted to its future attributive form 사용할, turning the whole phrase into “(the) to-be-used camera.”

Why is 카메라 marked with 를 in 카메라를 확인했어?

The particle 를 marks 카메라 as the direct object of the verb 확인했어 (“checked/confirmed”). It shows that the camera is what was checked.

Why is there no explicit subject in the sentence? Who did the checking?

Korean often omits the subject when it’s clear from context. Here, the speaker (I) is understood. In casual speech, you don’t need to say 나는 if it’s obvious whose action it is.

Why does the verb 확인했어 appear at the end, and what tense and politeness level is it?