Died when deacceleration then after start acceleration, now cranks but wont start

I changed and gapped the sparkplugs, checked the fuel filter and pump so far

What year and mileage? Do you have spark at the plug when cranking, do you have fuel pressure? compression? If this has a timing belt, has it snapped?

Is it cranking over WAY faster than normal?

If so, I’d say your timing belt may be a goner