HP Stream 11 – wifi rtl8723be

sources:
https://ubuntuforums.org/showthread.php?t=2319153

1.

1
 sudo apt-get install bcmwl-kernel-source

2.
You need to disable Secure Boot in UEFI (aka BIOS) settings, and Wi-Fi will work.
Secure Boot does not allow to load the unsigned proprietary driver.

3.