O.K. one question at a time, and I'll try to answer, but these are my opinions and may not reflect what others may advise or do.
should I replace the filter?
Yes, and you may need another one if the new one gets clogged up with gunk that's been in the tank for a while.
I'm also not sure how to put the atf in the spark plug holes should I drain the oil put atf in put the plugs back in put new oil in and then turn it over by pushing it forward in 4th and then let it sit over night and then change the oil again
That's a bunch, You can put the ATF in the cylinders with a funnel or piece of small tubing, The idea here is to get the rings lubed and maybe unstuck. Change the oil before you attempt to spin the motor, leave the plugs out, take out the coil to distributor center wire from the coil and distributor. Let the ATF do it's thing for 24 hours or overnight, before you try to spin the motor.
where do I drain the radiator from?
Take off the lower hose at the radiator, there is no drain cock on GT radiators.
I'm also not quite sure what to do about the brake fluid and draining/ cleaning that out...
Take the screen filter out of the top of the brake reservoir and get as much old fluid out as you can. Then get a 1-person brake bleeder hose, or an assistant, fill the reservoir and bleed the brakes in the following order, right rear, left rear, right front, left front. Keep checking the reservoir make sure it does not get empty during the process.
but spinning the motor till I get oil pressure?
After you get the engine to just turn over, there are no stuck or broken rings, put in a good battery and spin the engine with the starter for about 30 seconds, wait a couple of minutes, spin it again, using this cycle until you get an indication of oil pressure on the gauge or until the oil light goes out in the gauge. This means oil pressure is coming from the pump and lubricating the entire engine, supposedly.
but ground it these things I do not understand could you please clarify it for me for I'm not much of a mechanic
Grounding the coil means that there is no high voltage spark coming from the coil to the distributor. The same can be done by removing the high tension wire
from the coil going to the center of the distributor cap.
The big thing here is to make sure the rings are not stuck in the cylinders and break, the second is to make sure you have oil circulating through the engine before you start it. No oil means damaging the engine. HTH
Ron