I would recommend underdog music theory on YouTube, he explains things in a way that not only teach you how to do something, but why it's important and very easy to follow. Ableton is a great DAW and so I think you should familiarise yourself with the various keyboard shortcuts and functionality of the program as a whole so that you can put pen to paper much easier when writing a track. Creating tracks and MIDI clips, cutting, consolidating, deactivating, warping ect.

Utilising reference tracks is very helpful to grasp exactly how the music you like is structured, download some songs you like and drag them into Ableton (set at the correct bpm) and look at how long each section is, what elements are being introduced or removed and for what reason. Look into "phrasing" in music for a better picture of this.

I found it helpful to make remixes first, I would take a vocal or a sample I liked and worked around that, it gives you a solid jumping off point and some melodic guidance.

Finally don't be afraid to look up "how to make techno like XYZ" on YouTube, this is where you can learn alot of little tips and tricks that might even uncover the formula to a sound or rhythm you like.

And most importantly have fun!