4 Block the throttle wide open (how do i do this ?)
5 Disable the fuel and ignition systems by removing the ECM fuse and the IGN or C31 fuse. (i know how to do this just pull the fuse'* i got that) As an added precaution, detach the electrical connector from the coil pack. ( how do i do that ?)

These are the exact words for step 4 and 5 in my haynes repair manual for doing a cylinder compression check. My questions again are how do i block the throttle wide open? and what does it mean to detach the electrical connector from the coil pack? Is that just removing the spark plug wire from each coil in the coil module.

Blocking the throttle wide open will prevent fuel delivery (this is a trick to remember if you flood your car). Do it with a stick on the pedal, or tie the throttle full open under the hood.

Disconnecting the ICM connector (main harness) or disconnecting all 6 coils. Either way.

Or you can pull your ECM fuse to prevent fuel delivery. This will NOT prevent spark, however. The first few seconds of spark are provided by the ICM before the PCM takes over.

When I did the compression test on my old bonneville, I unplugged the ICM so there was no spark at all, I also had the accelerator sticked.
I can tell you, at a 152ish thousand miles, my old L67 had from 152-160 lbs in each cylinder.

so with the car off in park apply the gas pedal to the ground and hold it down. Could i just put a brick on the pedal to keep it down

I wouldn't. You need to be sitting there to crank the car anyway. Don't leave your fate in the hands of a brick.

is the ECM fuse under the hood in the max relay center. And which IGN fuse do i pull on the driver side fuse 5A Ignition (Run), Automatic A/C Control, Base Cluster or fuse 1D Ignition (Run/Crank), Chime, Cluster.

So how do i keep the pedal down to keep the throttle open

Please...use your foot. Or find a way to keep it open at the throttle body.

so when someone goes to crank it over just push the pedal down.

Get yourself a helper. Put them in the car. Meanwhile..pull the ICM connector as mentioned. Take out all the plugs.

Have them hold the pedal to the floor. Then crank a little. check your compression. Move to next cylinder and repeat for all cylinders.

Put it all back together.