Is the Fire HD 8 good enough for watching Netflix and Prime Video?

Yes. The 8-inch screen and 13-hour battery handle streaming well, and the speakers are adequate for a bedroom or kitchen. Picture quality is fine but not sharp, since the resolution is 1280 x 800.

Can I install Google Play and regular Android apps?

Not out of the box. It runs Fire OS with Amazon's Appstore, which lacks many Google apps. Sideloading is possible but unofficial and can break after updates.

How does it compare with the Fire HD 10?

The HD 10 has a larger, sharper 1080p screen and more power, while the HD 8 is smaller and easier to hold one-handed. Choose the HD 8 for reading and travel, the HD 10 for video and family use.

Should I get 3 GB or 4 GB of RAM?

The 3 GB version is fine for streaming, reading and browsing one app at a time. The 4 GB version keeps more apps open and feels smoother if you multitask or play games.

Does it take a microSD card?

Yes. A microSD card expands the 32 GB or 64 GB built-in storage, which is useful for downloaded video and music.

Yes. Amazon's kids profiles and parental controls are simple to set up, and the light body survives being passed around. A case is still worth adding.