Cranks but will not start?

My car was driving fine. I pulled into the store and cut the car off, went inside to get a drink, came back out and the car wouldn’t start. My alternator bracket broke. After replacing it the car still won’t start. Everything seems to be working properly. Have checked fuel pump and injector and fuses changed crankshaft position censor tried starter fluid still not catching. It turns over and acts as if it wants to start but it never does. It cranks but won’t start.