in our 24x22 garage have been installed 4, 8’ LED task lights onto the 10’ high ceiling. They provide very satisfactory task lighting. Your shed would only require 1 or 2. Believe they’re made in 4’ lengths too.

If roof is arched, will they still work?

Where did you purchase them?

@User - Bought those shown at HD a couple years ago. Around $100 each. I hard wired them using conduit - visable in the posted pix.

With your arched ceiling they should mount parallel to the arch.

Hope that helps.