Shrine vs. Temple

Which one do you think is the following one ⛩?

What do you visit in each?

仏様にお祈りする場所はお寺。
In Temples we visit the deseased, and Buddha. Cemeteries tend to be connected to them.

神社にはたくさんの日本の神様。
In Shrines we'll find Japanese Gods.

Are the main gates the same?

お寺の入り口には「山門」。
In Temples the main gate is called Sanmon in Japanese.

神社には鳥居。「鳥居」は神社の目印。
In Shrines there is the Torii an archway ⛩ which is Shinto Shrine's symbol. 神様のお住まいなので、くぐるときは頭を下げて一礼を。As Gods live there, when going under lower your head and bow.

However, these weren't as clear in the Meji era when made, and nowadays sometimes we can find Toriis in Temples. And main gates in Shrines (these are called sometimes「神門」shinmon,「楼門」roumon, etc.)

Who works in each?

お寺にいるのは、お坊さん。
Buddhist priests/monks (Obousan in Japanese) lives in Temples.

神社で神様に奉仕するお仕事は「神職（しんしょく）。
Priests that serve God at Shrines are called Shinshoku.

Information from: Hakken Japan