I have just installed Slackware. I am not new to Linux but new to Slackware.
I wonder how to install network in it.
After the Slackware installation, audio and network were not working.
This is how it looks like , no audio , network
Have you tried the instructions on the official network config site? I think most of your starting configuration questions will be written here.
By the way, if you really want to dive into Linux, don't go for Ubuntu cause you won't ever understand the core workflow of Linux systems. With slackware you will have a hard time learning how to do things, but if you learn something it will stick, go for it!