Hi and Welcome. My Name is ***** ***** I look forward to assisting you today with your question.
First you have to allow permission on your tab to install applications from Unknown sources. To do that, on your Tab go to Settings > Security and check the box next to” Unknown Sources “. Now on tab, open Internet app and go to this website --> http://m.aptoide.com/installer
Tap Install Now and an APK file will be downloaded. Open it using your file manager application and install it.
or download the installation file from your computer from here --> http://pool.apk.aptoide.com/1/aptoide-7.apk
or download Aptoide Lite apk from here --> http://m.aptoide.com/installer-aptoide-lite
Copy the files to your tablet using your computer (or email the files to yourself assuming you setup email on the tablet). Open the files and install them. Let me know if you have any difficulty.