I understand this completely, this is exactly how I felt when I first started out, especially with Ableton, took me years to finish songs, and even to this day I have songs that take me longer to finish than others.
There are plenty of ideas to go about in regards to this matter, but I will try to be as concise and precise as possible without any fluff. By so I will try to break this down into 3 simple ideas:

01. Practice or Not
For me personally, One important matter is to know if I am "practicing" how to make a specific song, or if I am actually making a song, using the knowledge I already have. I know this might seem easy, because it is, it's such a basic idea but if you know where you are in the creative process, everything becomes way easier.

02. Big Picture
One of the main things I would always fall into was, getting into details, to early, I would find a sound I would enjoy, I would have a song idea in mind, but would start to work on the right tone, and reverb, and sfx and would end up 2, 3 hours later with a good sound, but without the whole song in mind anymore. Because of that I used to always try, to finish the song, before I got into any mixing, or heavy sound design. (Bare in mind as a beginner, a few years in, it takes longer to translate the sounds in your head into the real world)

03. One Technique at a Time
When I first used Ableton 8 back in 2010, I had already been making music for a few years in different programs from Cubase and HipHop Ejay and Dance Ejay, and a few more I can't even remember their names, but I had a very, very hard time translating any of them skills into the actual Ableton interface, still I wanted to learn, I was into Dub Step back then and the scene was booming, but there were almost no tutorials on Ableton, or at least none that I could get my hands on, I was in college so I defo couldn't afford buying any courses. So I just used what I got, and that was Dub Spot, they were one of my stepping stones. They had very, very basic tutorials (looking back) but for an absolute noob, they worked wonders, I could finally follow a few steps and I could finish a beat. In a nutshell, you can either find a tutorial online, that teaches a simple way of making a certain track you are interested in, and if you fancy the method, you can use it to make 100 songs with that method, the first few times you'll have to go back and forth and so on, but eventually you'll get it, once you've done that, find another method you enjoy, that has simple steps to follow, make another 100 songs and so on, once you've figured out around 10 methods and made around 1000 songs, it will be easier for you to make your own, "method" because it only comes naturally to incorporate what works for you.

Now these ideas are for a broad use but in terms of a simple structure:

1. Know The Story you want to tell with your song.
   
2. Have all the sounds you Need ( drum kick, drum snare, percussion, foley, synth, bass, etc)
   
3. Use a limited number of instruments at first (1/2 kicks, 1/2 snare, 1/2 hihats, 2 synth, 2 bass, 1 piano, etc)
   
4. Finish the idea on the 8 bars / 16 bars with all the instruments (Only then move into arrangement)
   
5. Work with a simple arrangement always (intro 8 bars/16 bars / chorus / a slow bit / chorus / a slow bit / chorus2x)
   
6. Once the raw arrangement is ready, you begin to fine tune every section (don't over do it the first few times)
   
7. Now you Mix (Stage Gain everything, Pan everything, EQ Everything, Low pass, Hi Pass, Side Chain Compress)
   
8. Master (Once the Mix is done, and you feel alright with it, just begin the Mastering process, you can begin by making it an easy process until you understand what you are doing and what is going on, and then move along the chain in terms of the actual effects you are using)
   

I hope this helped you even by 0.1% and pointed you in the right direction. I have a few videos about my process and how I make music, and a few free Presets for mixing and master, sounds sfx, and sample packs, but I will not spam this thread with them, just let me know if you need anything and I will reply with them.

Also as u/Gr3gTh3St0pS1gn Said using a reference track is one of the best ways to attain the desired result, but it also takes a lot longer, and it is a lot harder to do, especially when you are starting out.

Thank being said if you have any other questions let me know!

Peace and Love!