The best sources to download and install whatsapp depends on the device and platform you use.
There are various sources to download whatsapp also noting that it is not necessary to have the application installed especially if you are using your personal computer. It’s a personal choice to either use web interfaces or the standalone application. To start of with mobile android platform
Playstore should be your number one option to download your application. It comes bundled in the android phone and all applications from Playstore are thoroughly reviewed to avoid entry of malicious applications in the store . The review to large extend helps reduce the amount of suspicious applications in the store
If you are an IOS user app store is your first option, download whatsapp application. The application reviews are more thorough than from playstore with an empathy to reduce substandard application in the playstore.
The third option is apkpure.com you can find applications that are not available in the play store here. Only android applications are available from apkpure store.
Contains apps for free in twelve different languages, applications from android ,windows and ios are all available.
You will only find mobile applications from the above named sites. You may need to access your whatsapp account via your computer , at a cyber cafe or even your friends computer.
To do this you have two alternatives ,either to use the whatsapp web interface or download a standalone application that is supported by your operating system. Both Windows, Linux and Mac operating systems are supported.
WhatsApp web is more advantageous over standalone applications as you don’t have to install any resources to your computer.
The one disadvantage of standalone or web interface is you must have possession of your phone and whatsapp installed in your device. This is in addition a security feature.