How do I add apps onto my Gabb Wireless phone?

If you can do it on your phone turn on unknown sources dont worry this wont put viruses, bugs or anything bad on your phone next grab your desktop computer it cant be a school chromebook ive tried didnt work anyways connect your phone to the computer and search up for example if you are trying to get snapchat you would search up SnapChat APK and once youve searched that up click on the apk download and go to your files on your computer and drag that apk over to your gabb wireless phone once youve done that go to your gabb phone and click on the apk and press download then snapchat should be on your device now you can do this with any app it takes some work but its all worth it in the end