It’s unlikely to speed up on Windows 11, and that’s assuming your device supports Windows 11. You may need to look to the hardware initially, and particularly the type of storage device, whether a mechanical hard drive or a more modern solid state drive
For an Intel CPU it must be at least 8th generation i.e i3/5/7-8nnn for Windows 11. I do not know about AMD.
eBay sellers etc 'fudge' Windows 11 onto older systems but as I understand it will not update.
For Windows 10 both at least 8GB memory and a solid state drive make a big difference. If you have limited funds but only 4GB memory or a tradition hard drive you will gain by upgrading. Even if you have to dump the existing memory 8GB and a 240/250GB or even 480/500GB Sata SSD I guess at most £50 on eBay.
I dumped Windows for Ubuntu (Linux) a few years ago and it does everything I want with less hassle. I think Windows specific software is the only reason to use Windows.
I'm lumbered with Windows 10 at work. They will have to invest in new hardware for Windows 11.
For home when Windows 10 and the bi-annual upgrades were announced I investigated Linux and have not looked back. Initially Mint but now Debian with the KDE plasma desktop. I would have stayed with Mint expect it will not rescale the screen well. I used to only buy laptops with a 1366 x 768 screen but most now are 1920 x 1080 while the few that are not are low specification. The laptop I am using now is i5th 7th generation but an i5 4th generation with 8GB ram and a SSD isn't that much slower to start up and for website browsing.
I set up dual boot with Windows 10 but have never needed to use it. I have one that is an i5 8th generation so sometime will set that up with Windows 11 and Debian.
I have a laptop that never goes on line running Windows 7 for a few applications. Also a desktop PC that is dual boot Windows 98 & XP that is primarily used for DVD editing after VHS to DVD transfer using a recorder and scanning. While it keeps working no incentive to set up a replacement running Windows 7 / 10 / 11 or buy a new scanner.