Jailbreak:
https://www.firesticktricks.com/jailbreak-fire-stick.html

Step 1: Install APK Downloader on FireStick
1. Go to the home screen of your Amazon Fire TV Stick.
2. Select Find in the middle bar, followed by Search.
3. On the search window, type the app’s name, Downloader. 
   Click Downloader in the search suggestions.
4. Click the Downloader icon on the next screen.
5. Choose Download (or Get) on the next window.
6. Wait for the Downloader app to download and then install it. 
   Then click Open to launch the Downloader app.
7. Dismiss any prompts displayed when you use the Downloader app for the first 
   time. But if it asks you to give it any permissions, ensure you Allow them all.

Step 2: Setting Up FireStick for Jailbreaking
All you need is your FireStick, its remote, and an 
internet connection.
1. Power on your Amazon Fire TV Stick and wait for this home screen to load up.
2. Select the gear icon or cog icon in the middle bar (on the far right) to open
   Settings.
3. Now, choose the option My Fire TV.
4. On the following window, click Developer options.
Note: If you do not see Developer Options, go to Settings > My Fire TV > About.
Now, select Fire TV Stick and click it 7 times to enable Developer Options.
5. First, switch ON the ADB Debugging.
6. Next, click Install unknown apps. This setting permits you to download apps 
   from outside the Amazon App Store.
7. Click Downloader and turn it ON.
8. Press the back button on the Amazon Fire TV remote. It will take you back to 
   the Settings window. Open Preferences.
9. Open Privacy Settings.
10. Turn OFF the following options to stop sharing the usage data after you 
    jailbreak Fire Stick in the Privacy Settings:

    Device Usage Data
    Collect App Usage Data

11. Press the back button one time. You should now be back in the Preferences 
    window. Click Data Usage Monitoring.
12. Now, turn OFF the Data Usage Monitoring setting on the next screen.