Dual boot CentOS 8 Stream and Windows 10

I have installed CentOS 8 along with Windows 10 as dual boot. Windows 10 was there first. After installation Windows is only available in the GRUB in recovery mode. How do I fix this?

So far I tried doing the recovery, but it failed with some error.
Also tried following instructions here: dareneiri.github.io/Configuring-Grub-2-on-CentOS-7/

However, I fail to get access to /grub.d on step 3 of those instructions.

I am new to Linux, so I might be doing something wrong. When I cd there, it just tells me “Permission denied”. Using sudo before cd doesn’t seem to do anything.