There is a way to use my Galaxy tab s like a wacom table, on linux?
There is a solution now: Weylus. Screen mirroring, pressure sensitivity and multi touch is supported.
Instructions for installation and running can be found in the readme, make sure to follow through the instructions regarding uniput otherwise things like pressure sensitivity will not work.
Disclaimer: I am the creator of this project.
You can use your Android device as a Drawing tablet like Wacom Devices with the following options:
The GfxTablet project is an Android app that allows you to control a virtual Network Tablet on Linux, in this case in Ubuntu. (Last release: 19/Nov/2018, not maintained anymore but it is worth to try).
SketchBus turns your mobile device into a drawing tablet, it is easy to set up, very precise and cross platform (Linux, Windows, Mac, iOS and Android).
XorgTablet, another solution that allows you to use your smartphone or tablet to draw or write in your Linux PC, here is a quick overview (in spanish).
RemotedroidServer, just install the client on your tablet, and then connect to the local IP of your running server. It sends mouse movements, left click, right click and keyboard strokes. The server doesn't require installation, is a simple ".jar" file. You can run it executing:
java -jar /path/to/RemoteDroidServer.jarTelepad, it allows you to control your computer remotely from your smartphone.
Slide App, it allows your Android tablet to be used as a Drawing tablet for graphics designing on Linux, in the description of the video you can find all the links to download the app.
Hope it helps.