Why is my 2004 mercury monterey wont start and before that the power sliding door stop working?

it's not open and when I tried to start the engine all the lights on the dashboard are on it's not open and when I tried to start the engine all the lights on the dashboard are on

There is a very distinct possibility it's the Neutral Safety Switch on the Transmission. Although this sounds like a big deal to diagnose and change it's really not.

Assuming that it's not a bad or weak battery...

When this is happening try jiggling, bumping, or tapping around on the shift lever.
If the vehicle then starts then chances are the sensor is either bad, going bad or simply out of adjustment.

Replacing it isn't a big job either.
If you look at the air intake on the engine you'll notice a tube or what appears to be a snorkel of sorts. Below that on the transmission is the sensor. It is a u or acorn shape and is distinguishable as being the only thing with a rod and lever on it.

But, before you replace it loosen the two small bolts which hold it on and try adjusting it a little. Adjustments are made by slight rotations either clockwise or counterclockwise.
DO NOT MAKE MAJOR ADJUSTMENTS, LITTLE BY LITTLE.

If it is bad, then it's simply a matter of removing the linkage on top and the holding bolts. Alignment can be a little tricky but there are you tube videos out there which detail everything. Patience, a flashlight, basic socket, wrench set and something to magnify the aligning marks such as a cell phone camera is about all you'll need. There is a very distinct possibility it's the Neutral Safety Switch on the Transmission. Although this sounds like a big deal to diagnose and change it's really not. Assuming that it's not a bad or weak battery... When this is happening try jiggling, bumping, or tapping around on the shift lever. If the vehicle then starts then chances are the sensor is either bad, going bad or simply out of adjustment. Replacing it isn't a big job either. If you look at the air intake on the engine you'll notice a tube or what appears to be a snorkel of sorts. Below that on the transmission is the sensor. It is a u or acorn shape and is distinguishable as being the only thing with a rod and lever on it. But, before you replace it loosen the two small bolts which hold it on and try adjusting it a little. Adjustments are made by slight rotations either clockwise or counterclockwise. DO NOT MAKE MAJOR ADJUSTMENTS, LITTLE BY LITTLE. If it is bad, then it's simply a matter of removing the linkage on top and the holding bolts. Alignment can be a little tricky but there are you tube videos out there which detail everything. Patience, a flashlight, basic socket, wrench set and something to magnify the aligning marks such as a cell phone camera is about all you'll need.