I can relate to this.

I've been doing nothing work and study related for approximately 6 months in the past year.
Not so long ago, i had a turning point. I was, just like you, always searching for something to do, but nothing I did satisfied me. Things that satisfied me before became less satisfactory. The searching had to stop. So I decided not to do anything anymore if it came forth out of unhappiness of the moment. It definately helped. Sometimes I just even stare at the sky, or at plants and insects. Often I go for a bike ride without any plans where I want to go, read something etc...

It's really much more important how you do something, instead of what you do. Just try to find the joy within the moment. Then it doesn't matter that much anymore what you do.

I recommend you reading: "The power of Now" from Eckhart Tolle.

Further on you can just take walks, buying a bicycle isn't a bad idea, I ride my bicycle all the time (Though, what interests me might not interest you)