Node js sending thousands of requests and handle data the most performance way

I had express server with service which is doing legal scrapping. He is sending many requests , then handle data , parse it and give it to another service.

I heard about that fastify is much faster than express so i changed to fastify , added some perfomance now- logging, but i dont see any diffrence. I was trying to change fetch to axios but still i don’t see diffrence. In my case there is simple for in loop with pages number index. Any idea how i can can more performance in fetching data?