maybe just start with envisioning your life one year from now. It takes practice. Then maybe later when you’re ready, start envisioning your goals about what you want 3-5 years from now. but of course, life can change and we go with the flow.
i’ve also had a difficult time with envisioning anything more than 3 years from now. But I’m confident I’ll know what I want when i’m ready to start envisioning 5 years or longer.
I think there was something in the GTD book about Maslow’s hierarchy of needs. You gotta think about survival (eating and shelter) first before you can get up to the other things. In GTD terminology, work on your runway stuff first (tasks). Then you can think at a higher horizon of focus - the projects. Then work your way up to Areas of Responsibilities. I forget what the higher horizons are but they tend to be further out into the future (3+ years) up to your life vision(the ultimate question - what am I here on this planet for?).