2000 sunfire pontiac

So my car had lights battery was tested battery us
good the starter was bad I replaced the starter my
self and when I connected the battery back one of
the wires was split. So I cut the split rewired it
hooked it back up and I still have the same
problem where my lights turn on but when I start
the engine it silent when I turn the key and won't
start . my question is what could the next problem
be. Friends say it could be the fuse from the split it
had and shorted out.