you need to check network tab of chrome developer tools and waterfall specifically in it to see difference between requests

@ToygerAs I understand it, this is a capacity problem on the server?
I tried changing the server location to the nearest one.
It was Mumbai, but the delay rate increased to 5 seconds. Do I need to upgrade to a higher power plan?

such drastic speed change because of domain change is impossible.
I see from screenshot that other resources are pretty quickly downloaded but your request generate response almost 2.5s which is a lot, you need to optimize your code, maybe you have here some external requests or some big data processing, but 2.5s is huge

I don't need to increase the power in my tariff plan?

https://www.poly-house.kz/kz
This is my website

if you want you can, but I doubt that it will help a lot.
most likely it's some external request, or complex calculation that add such big delay