Please help me, my dell laptop wont turn on

What happened before the laptop seemed to die, the more details the better! Also make and model please, thanks!

Try pulling the HDD out, the RAM, and leave the battery out. Make sure that the Power Supply is for that model laptop or if it is aftermarket that it has enough Wattage to power the laptop while the battery is removed. If the battery has gone bad this can cause boot issues sometimes. If there is like a watch battery under one of the panels in the laptop try removing that as well.

you can try to boot without the RAM and Hard Drive and see if you at least get any error beeps. Also, let me know what the lights on the laptop look like, plugged in with and without the battery.

When the light comes on does the fan turn on and stay on or does it cut off?

Well, I hate to say this as I love diagnosing problems and feel accomplished resolving them, but the laptop may be beyond basic solutions at this point. I had a Gateway laptop that was doing similar problems and I was completely unable to resolve it. I concluded it was motherboard failure.

However I have come across a few HP laptops that had similar symptoms and upon replacing the battery the computer booted up like nothing was wrong. If you don't mind throwing a little money at it you could always find a cheap used or replacement battery from eBay to see if that would resolve the issue. If I was present I would eventually take the laptop apart and start with the montherboard, plugging up the basic components needed to run; screen, processor, and one stick of RAM..

If you arent tech savvy enough to do that I may take it by a computer store to have them diagnose it, some will do this for free and not charge you if they cant figure it out. Sometimes its better to have a tech present to diagnose stuff as they can physically see whats going on.Only thing at this point would be to try one stick of RAM , then test with another slot. Wish I could be of more help..