Client doesn't lag but Server does lag?

You might think servers don't get lag, but they actually do a lot.

So when I test out my game in two server and client windows. I see that the client's FPS is working fine about 60fps, but when I switch to the server, and oh boy, it's like 5fps or lower. And from that server lag, it slows down everything that the client sees like moving things get slowed down by 50%, and touch events takes 5 seconds to trigger and from waiting 0.1 seconds to wait 1 second

So apparently the server is lagging out badly, my game has 3000+ parts, but that's still nothing compared to those big games on the front page. Here are some images of my game: Image 1, Image 2, Image 3

And also, removing the 502+ coins or not making them rotates still makes the server really laggy. I think it's because of the intenseness in my game, there's quite a lot of particles and touch event in it. I even use module scripts to shorten big scripts. A quite suspicious thing is the activity of the cloud resizing scripts (the cloud's size changes over time to make it realistic), their activity is like 20+%