It sounds like you have a pre-owned desktop with some existing configurations. Here's a step-by-step guide to help you install a new operating system:
1. Preparation
- Make sure you have backed up any important data if there was any.
- Determine if you want to install Windows, Linux, macOS, or another OS.
2. Boot Priority
- It's a bit odd that "Microsoft Office 8 Pro" shows up in the BIOS. This might be a naming error or misunderstanding. BIOS usually lists boot devices, not software like Office.
- Ensure you set the boot priority to USB or DVD, depending on where your installation media is.
3. Installation Media
- For Windows: You can create a bootable USB using the [Windows Media Creation Tool](https://www.microsoft.com/en-us/software-download/windows10).
- For Linux: Download the ISO file of your preferred distribution (like Ubuntu) and use a tool like [Rufus](https://rufus.ie/) to make a bootable USB.
- For macOS: It's tricky to install macOS on non-Apple hardware, but if it's an Apple device, you can use macOS recovery or create a macOS bootable USB.
4. Install the OS
- Insert the bootable USB or DVD into the desktop.
- Restart the computer and boot from the USB/DVD (you might need to press a key like F12, F8, or ESC during startup to choose the boot device).
- Follow the on-screen instructions to install the operating system.
5. Post-Installation:
- Once the OS is installed, it's a good practice to install all updates.
- Install necessary drivers, especially if you're on Windows. You might need to visit the manufacturer's website to get the latest drivers.
- Install necessary software and restore your backed-up data.
6. Office Issue
- If by "Microsoft Office 8 Pro" you're referring to an old software installation or a weird BIOS entry, you may want to reset the BIOS settings to default or update the BIOS firmware if there's an update available from the manufacturer's website. This might correct any oddities or errors.
Remember to always exercise caution when making changes to your BIOS and during the OS installation to avoid potential issues. If you're unsure about any step, please ask for clarification.