Hi
No, that model of Apple Watch (not iwatch) is not currently supported there.
Apple Watch Series 3 (GPS + Cellular) availability
Apple Watch Series 3 (GPS + Cellular) is not currently available in Namibia.
Apple advises that Apple Watch Series 3 (GPS + Cellular) will become available in other countries this year, but it has not yet specified when and where. I suggest that you monitor the Apple website for further information regarding potential availability in due course:
Choose your country or region - Apple
I'm afraid that, in the meantime, no-one here can tell you anything about Apple's unannounced plans. You are not talking to Apple here - this is a user-based technical support community.
Buying in a different country
Apple Watch Series 3 (GPS + Cellular) is not locked to any specific carrier and has a built-in eSIM that copies information from the iPhone's SIM card.
The built-in cellular features require a carrier plan for your iPhone in your country of use that specifically includes support for Apple Watch Series 3 (GPS + Cellular), including the carrier activating the device on the plan.
If buying Apple Watch Series 3 (GPS + Cellular) in another country, then, in order to use the built-in cellular feature, you would need to buy a model that supports the relevant LTE and UMTS bands for your intended country of use and your supported carrier there.
There are three different regional versions of Apple Watch Series 3 (GPS + Cellular), each supporting different LTE and UMTS bands, as detailed here - Apple does not currently list any supported carriers for Namibia:
Apple Watch - Carriers - Apple
If in doubt, I suggest that you contact your intended carrier to ask whether any given model can be used on their network with a plan that they may offer or plan on offering for iPhone that supports Apple Watch Series 3 (GPS + Cellular).
Apple Watch Series 3 (GPS + Cellular) can be used without activating the built-in cellular feature, in which case it functions like a GPS-only model, in conjunction with an iPhone 6 or newer model of iPhone (running the latest version of iOS) and a service plan from any carrier.
The built-in cellular features cannot be used when roaming. For an Apple Watch purchased elsewhere, warranty service may also not be available.
Is iwatch series3 cellular supported in Namibia?
