Your natal chart is a map of where the planets were when you were born. It’s fixed. The planets then continue their orbit on a circular path.
A “transit” occurs when a planet in the sky moves into a position that hits a certain angle with one of your natal planets. When a planet in the sky is 90 degrees from your natal planet, it’s called a square. “Pluto is squaring my natal Moon.” When a planet in the sky is 180 degrees from a natal planet, that’s an opposition. “Jupiter is opposing my natal Mercury.” A transiting planet that is 120 degrees from a natal planet is called a trine, etc.
Since your natal planets are in different positions than mine, your transits are unique from mine.
If you are studying, you can get a year-long list of the transits to your chart with interpretations here. This will help you learn how to interpret the effects of transit to your natal chart.