Nice game. It's simple design but feels polished. I appreciate that you give players a few attempts when hitting incorrect blocks -- but maybe hitting the correct blocks should make them disappear on first hit so it feels like less of a chore.
The level with the U heavily carved out was difficult because I wasn't sure from the template on the left which top and bottom blocks to carve. I ended up carving out a U a the wrong level and died. (could fix this by adding a border to the template to give the player a visual reference)
Well done!