How hard is it to upgrade the cpu on a lenovo S510p touch?

My laptop is laggy and I wanted to get the i5 and throw it in there. Is there one that's not so power hungry but still fast? I know my battery life will not be as good. The laptop has a pea shooter i3

1. Laptops use special mobile CPUs that are not available for the general public to buy.
2. Laptops have the cpu fused to the motherboard. And as such can't remove or upgrade the cpu.
3. It would be cheaper to buy a new laptop than it would be to try and upgrade any major component in most laptops.

You should try doing a clean install of windows without all the bloat. I have the same laptop and it is super snappy after doing so