1997 ford taurus put car in drive and in reverse and mash on gas acr only move a little in gears

Sigh. The most likely answer is the MAF Boot (Air Mass Sensor) has a crack in it, AND, your motor mounts are worn out. When you put it in gear, there is a significant torquing of the engine, and it tends to try and "move" or twist to get the tired turning, but until you drive that isnt happening so the transmission clutch or torque converter eatst he rotation and allows it to idle. All find and well, HOWEVER, if your motor mounts are bad, then the initial twisting force when it goes into gear causes the engine to move enough that a crack in the MAF sensor will open, causing a massive air leak that tells the computer the wrong amount of intake air, it then sends the wrong amount of gas...engine only runs on right air and fuel. Engine stalls.

When putting in 1st gear, the lower gear coupled with quicker takeoff can sometymes prevent the initial stall and as the engine untorques when it moves back, the crack closes and returns to normal (ish)..
There could also be some electronic answers...but as its very common and easy/cheap to check, Id start there,.

sounds like you have a manual transmission. ?
Worn Clutch plates will give these symptoms
The clutch plates rub together and provide connection between the gear box and the drive shaft if not worn.
Also check the cable for the clutch is not loose and needs a surclip to hold it in at the firewall.
Check if Hydraulic Clutch that there is adequate clutch fluid if low might have leaking clutch master cyclinder

I have experienced this in a car I owned.
Not a lot of fun . Resulted in needing a Tow to repair garage and new clutch was AUD $1200 a couple of years ago.

need to check the shift cable at the transmission. a little plastic bushing is used to hold the cable in place and it breaks.

Heavy load in park sounds like a transmission issue. The torque converter and transmission pump are still spinning in park

Have you checked the transmission/gearbox fluid is at the correct level ? This will also cause this. Hope this is of help.

sounds like you are low on fluid if not then it's time for AAMCO to take a look

it could be that the tick over is two slow in brive,,,
set it up to tickover at 850,,950 rpm (in drive)
or it could be a gear box fult like the drive plate has a crack in it,,,letting the torque converter slap about,,,
chech tick over first,,, bont adjust tick over in gear unless the brakes are held hard on,,,

SOUND LIKE THE TRANSAXLE DRIVE CHAIN AND DRIVE SPROCKET BEARINGS IS SHOT.

Start with a complete flush of the trany and torque converter, and a filter replace. That should fix the problem, but the Taurus has a bad reputation for trany's going out frequently.

If your in gear (D) for example and you hit the gas, engine revs, but car doesn't speed up, it's a problem with your transmission, and the first thing you can do is have the fluid level checked, and add fluid if needed. If that's not the cure, take it to a transmission shop & have it diagnosed.