2008 Smart ForTwo won’t start

Worked fine the night before. Would not start in garage next day. Replaced battery, fuel pump fuse is good. Still won’t start.

What do you mean “won’t start”? It cranks normally but won’t fire? If it cranked, why did you replace the battery? Was the check engine light on the day before when it was running?

If it cranks, spray some starting fluid in the intake to see if it fires and runs for a second. If it does you have a fuel problem. If it doesn’t, likely an ignition problem. Possibly a crankshaft sensor.