Sure. Research, read, FAQs.
But I'll be kind and say: Hello, you can downgrade the FPS by changing th spring. A weaker spring will give less compression, leading to a lower FPS.
Now go and read the stickied threads on the newbie section.
K3vX | Airsoft Gunsmith/Gun doctor in training.
Feel free to contact me in your preferred language and I'll gladly answer.