Just my two cents, even if it didn't prompt to install Windows 10 2004.
You can do a clean install but not upgrade to prevent any issues
during the install.
(*Clean install is using USB installer to install from fresh but
not OS reset which is different.)
Remember to download all the drivers from Lenovo website,
during the setup disconnect the laptop from internet.
Load all the drivers before connecting to the internet.
https://pcsupport.lenovo.com/sg/en/...series/legion-5-15arh05/downloads/driver-list
This to also ensure driver like graphic are installed with the correct
version.
Once you do a clean install, speed will be vastly different since
laptops have bloatware.