Firmware vs RouterOS

Do RouterOS updates also update Firmware?
I am using RB750Gr3’s as simple DHCP appliances with no internet connection.
I have sorted through WinBox to manually update the RouterOS.
Is there a way to manually update Firmware or is it also updated by a RouterOS update?
I haven’t yet found any downloads advertised as “firmware.”
I’m just trying to be thorough.

Yes. But not automatically. Read the manual about the routerboot.

Essentially when you update ROS, firmware update file is prepared for that device … but you need to execute firmware update manually.

Thanks to you both.
I’ll read about RouterBoot.

Using the terminal within WinBox, my Routerboard Firmware now has the same number as the RouterOS;
6.43.2
I’m hoping that is correct, that they would match? Can someone please confirm that is correct?
Thank you.

Yes, matching versions are fine.