I don't have a Fire tablet or any Alexa-enabled device, so I'm fumbling in the dark here. However you should be able to view all available games by going into 'Skills' on the app. (This link refers primarily to the Amazon Echo but it also mentions "or other Alexa-enabled device":
https://www.pcmag.com/how-to/how-to-play-games-with-amazon-echo-and-alexa )
To make free calls using your Fire tablet, you'll need Skype (or possibly a similar app, although Skype is by far the most well known):
Amazon.com User Recommendation?tag=stufftv-21
Skype lets you talk to (or video call) any other Skype user, anywhere in the world, totally free of charge. However to make calls to mobiles and landlines, you'll need to have a paid Skype subscription
https://www.skype.com/en/international-calls/
or to buy Skype Calling Credit:
https://secure.skype.com/en/credit
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