Mercury Mountaineer 2002 won't start up.

I have a Mercury Mountaineer that won't start up since yesterday. This Thursday after work, my engine started making weird noises. That's when I noticed the "check gage" light was on and realized my oil pressure was low. I put 5W 30 oil in, but the oil pressure did not rise on my dashboard. On Friday while driving, my car cut off on the highway and then again on the rode. When it cut off a third time, it did not start again. My father had to help me push it back. Right now, my mechanic is having trouble diagnosing the issue because the engine is getting gas, the battery Is working fine, it's firing, gas pressure is good, and we just put in new spark plugs. The oil pump and gas pump is working. I don't know what the issue is. Please help.

What kind of compression do you have?

Sorry, I am a new car owner so I do not know what you mean.

Can anyone help me?

Update:

My 2002 Mercury Mountaineer still won't start up. My mechanic could not figure it out and it seems he abandoned me and my car. I am on a search for a new mechanic, but I would prefer to fix this issue on my own with the help of this forum. The "check gage" light is still on with my oil pressure gauge on low. The battery still has power and I am getting fire. I smell gas when I try to start my car and when my mechanic was checking to see if the engine was getting gas by pushing a screwdriver in some hose, gas squirted out. Everyone seems to be focused on trying to start the car, but they seem to ignore the fact that the oil pressure gauge is low and that the engine was making weird noises before it shut down. I even screeched. Can someone please help.

Have you checked the oil level and condition of the oil?

-Rod

I have checked the oil level and it is good. However, I did not check the condition of the oil. How do you do that?

Also, there are no leaks coming from my car. I put oil in on Thursday and the oil level did not drop at all.

I put oil in on Thursday and the oil level did not drop at all.

Does the truck use oil, and that's why you put oil in on Thursday, or did you perform an oil change on Thursday? -Rod

The truck uses 5w-30 oil and I put more oil in, I did not change the oil.

How often do you need to add oil to the truck between oil changes? Is it something like you need to add 1 quart of 5w-30 every 1000 miles, etc.?

-Rod