Why won't my car start, but it'll turn over?

Sometimes my car will not start, but it will turn over. Then after a few hours, or
even days, the car will somehow start. Figured out there was a slight oil leak at
the Oil Pressure Sensor. I fixed that and it started right up and it kept working for
a couple of weeks. Then it started happening again, no start but will turn over. I
found out that it could be the Ignition Coil. I replaced that with a part that I found
on Amazon. It worked but it lasted only a month. A week ago, I went to start my
car. It started for like a split second and then it died. I tried to start it but it just
turns over. A few days go by and I would try to start it every now again. Same
thing... turns over but it doesn't start. The first thing I thought to replace was the
Ignition Coil, got a new one - from Amazon - but it still didn't work. (When I got the
new Ignition coil, I tested to see if there was spark and there wasn't any.) So I
sent both back thinking they didn't work. I have been putting off, finding another
one because I don't wanna waste my time and money if it isn't the problem.
Maybe I should just replace the whole distributor, rather than replacing the coil.
Some guy told my dad that it might be the Ignition Spark Control Module. I've
never heard of it and I haven't seen anyone else mention the module. It's in the
distributor itself, which I replaced the whole distributor a few years ago when my
car wasn't turning on. It's a small part and it doesn't cost a lot on Amazon but it
doesn't look like it'll fit in the distributor even if Amazon says it will. So I really just
wanna know what the heck is going on and how can I fix it?

It never dies when I drive it but it's when I try to start it when it won't start, it only
turns over.