No Network devices available on a cheap HP Stream

hi arcu ;-)

Trisquel has wireles-tools, and Network Manager as default, you may need to get a dongle from https://www.thinkpenguin.com/catalog/wireless-networking-gnulinux
in order to get wifi working.Network Manager will display information about your connectivity

in a termninal :

$ route

all interfaces

$ ifconfig -a
wifi

$ iwconfig
To see what chipset your wifi card
$ lspci | grep Network

https://h-node.org/
The h-node project aims at the construction of a hardware database in order to identify what devices work with a fully free operating system

https://help.ubuntu.com/community/NetworkManager
https://help.ubuntu.com/community/WifiDocs/WiFiHowTo

If it's Broadcom, it almost certainly won't work without non-free firmware.

You'll probably need a USB wifi dongle.

This one should work (TP-Link TL-WN722N, Atheros AR9271 chip):

http://www.tp-link.com/us/products/details/TL-WN722N.html

https://trisquel.info/en/forum/14-fantastic-wifi-adaptor-tp-link-tl-wn722n

Caveat:

If you want to support free software in devices, it's safe to go with Thinkpenguin, even if it's more costly to do so. TP-Link gives no guarantee that their devices will work with libre software. They may change the chipset at any time without notice, thus rendering the hardware non-functional with libre software, and still retain the same packaging and brand name. Buyer beware.