Before you can properly begin your manly projects your gonna need a man cave = project 1. Build a shed or drywall the garage, false ceiling, wooden floor, electrics, fridge etc. That should keep you busy a few weeks.
Then you’re gonna need to build a workbench, cupboards & shelves to store all the tools it took to build the man cave and left-overs (rule no.1 you never throw anything away) = project 2.
Then you can start thinking about a proper project, using all the shed off-cuts to make garden furniture / sculptures, kitchens etc. Before you know it you’ll be on an episode of grand designs.