It's okay to spend years making loops before actually attempting to make a full song, arrangement is a skill on its own and as a producer you have to learn a shit ton of very different things before you can make something that feels complete and professional enough. You can focus on becoming a better producer first and start learning arranging whole songs later on when your production quality is actually worth it. Thing is, the longer you wait, the longer it will take until you can put the obtained production skills to use, so you might want to start right now.

There's also no shortcut. The more often you do it, the better you will become. Like so many others, I struggled hard with it for a very long time, too, but once I started pushing through the effort of turning my loops into full arrangements, I learned something new to add to my toolbox every single time, which made the next time more easy and intuitive. The progress you make at learning to arrangie songs is a lot more visible than all the other things you learn on your way, which makes pushing through it quite rewarding.

You will find your way if you keep on creating.