How To Reformat External Drive Which Has Windows IOS On It

[Hikermann]

OPERATING SYSTEM
Windows 10 Professional (x64) Version 22H2 (build 19045.6466)
System Model : HP HP ProDesk 600 G3 DM
SYSTEM MODEL
HP HP ProDesk 600 G3 DM
Enclosure Type: Mini PC
PROCESSOR
2.80 gigahertz Intel Core i7-6700T
256 kilobyte primary memory cache
1 megabyte secondary memory cache
8 megabyte tertiary memory cache
64-bit ready
MEMORY
15.88 Gigabytes Usable Installed Memory
BOARD
HP 829E KBC Version 06.29
STORAGE
4.51 Terabytes Usable Local Storage Capacity
3.59 Terabytes Local Storage Free Space
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MESSAGE:

Although I have successfully formatted/reformatted drives in the past,
1. I recently copied my Windows 10 IOS to a Seagate 2TB external drive
2. That drive now does not show up in Windows Explorer
3. But it does show up in Disk Management
- Basic
- 1863.02 GB
- Online
- Unallocated
4. Typical
- open Disk Management,
- right-click on the drive
- select FORMAT
is not possible because FORMAT does not show as an option
5. Only options that appear are
- Convert to Dynamic Disk
- Convert to GPT Disk
- New Simple Volume
6. Any info about why FORMAT or REFORMAT do not appear?
7. Any suggestions about how to clean the disk so it can be used?

Many thanks. Appreciated.