〜と (whenever)
when, whenever, if (then naturally)
Verb dictionary form / ない form + と
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Dictionary form + と says that B follows A naturally, every time: このボタンを押すとお湯が出ます, "press this button and hot water comes out".
It's for things that always happen: how machines work, laws of nature, habits and directions. 春になると桜が咲く, "when spring comes, the cherry blossoms bloom"; まっすぐ行くと銀行があります, "go straight on and there's a bank".
The limit: the result can't be a request, an invitation or an intention. 駅に着くと電話してください is wrong; use たら.
In the past, と describes what happened next, often a surprise: 窓を開けると富士山が見えた, "when I opened the window, there was Mount Fuji".
Examples
このボタンを押すと、お湯が出ます。
Press this button and hot water comes out.
春になると、桜が咲きます。
When spring comes, the cherry blossoms bloom.
まっすぐ行くと、右に銀行があります。
Go straight on and you'll see a bank on the right.
私はコーヒーを飲むと、眠れなくなります。
Whenever I drink coffee, I can't sleep.
窓を開けると、富士山が見えました。
When I opened the window, there was Mount Fuji.