How to make a menu in the bootloader so that Windows starts first, and not centos?

Question

linux

Hello. I installed Centos7 alongside Windows 8.1. At first I had a problem that after the successful installation of Centos, only Centos itself was in the bootloader menu, but there was no Windows. It was necessary to return the bootloader to the menu, Windows 8.1. Returned with grief in half like this:
sudo vim /boot/grub2/grub.cfg
menuentry "Windows 8" {
set root='(hd0, 1)' #adjusted the second digit here thanks to advice How to restore Windows 8.1?
chainloader +1
} I
saw Windu in the boot menu, and it started normally. Only now another problem has appeared, I want not Centos 7 to be launched first, but Windows 8.1, and of course the choice of OS to remain))). The question is, how can this be done?
Addition to what I tried to do, (Google):
1) grub-customizer, didn't see this command, and even as root couldn't install it, can't find this install.
2) update-grub - does not work. writes something like this: bash: update-grub command not found.
3) I don't know what to do next. I count on your help

Answer 1

sudo grub2-set-default "Windows 8"

Answer 2

Have you tried editing grub configs? Googled in a couple of seconds
Setting up grub