Inflation is caused by money becoming worth less due to more of it being available.

One of the main ways people get access to more money, is by borrowing for institutions like banks. If the bank is loaning out money for 0% interest rates, this will stimulate the economy to grow, as people are borrowing and spending more money.

However, borrowing money for 0% interest would mean that there is little incentive for people to think to much about what they are borrowing, so too much money is released into the economy, decreasing the value of money overall. If everyone has 100$, really nobody as 100$. This causes the bubbles you’ll hear everyone talking about, and is why companies like Tesla are overvalued. People can invest tons of money into them for little interest.

So when the Fed increases interest rates, people will start borrowing less, as the monthly payments will make them think a lot longer about what they want to invest into. So higher interest rates means less borrowing, means less money being freely available in the economy, meaning the strength that 1 money is more, decreasing inflation.

TLDR: more borrowing due to lower inflation, the less money is worth(inflation). Less borrowing due to higher inflation, the more money is worth(deflation).

Sorry if this is a bit all over the place, hope it kinda helps