Hi @mohammedsani
Is there a Google account associated with the phone?
If not then you cannot download apps from the Play Store.
To install apps from other sources have you enabled the ''Install unknown apps'' setting?
Here's a [https://www.youtube.com/watch?v=yDILrNxk2iM|video] that may help. I realize that it is not the exact same model as your model but usually manufacturers don't change things between different models.
Also ensure that any app that you're trying to install is compatible with the Android OS version installed in the phone.