The correct answers are "I ate deep-fried tarantula in Cambodia in 2018." and "I have tried almost every street food in Bangkok."

We use the Present Perfect to talk about general life experiences when the exact time isn't important or isn't mentioned ("I have tried...").

However, the moment you mention a specific, finished time in the past—like in 2018 or when I lived in Bangkok—you must switch to the Past Simple ("I ate", "I tried").