98 chevy pickup wont shift out of first onless you lift out of the gas pedal and shifts all the time messed up on the hiway

There is a switch on the brake pedal that you must fix. This allows you to shift out of park only after the brake is applied.
Assuming since it goes in Park that its an automatic otherwise if its a shifter on the floor there is an actuator under the rubber around the shifter which if you lift it up yiou will find that you can manually move the piece which allows you to move the shifter.

Could be a vac modulator problem.

If it is an auto matic trany, it could have went into limp mode. This is usely fixed by replacing the shift control module. it plugs into the side of trany pretty easy to locate when you have the new one in your hand.

Check the adjustment of the transmission T.V. cable. Sometimes they also stick. Try driving it at 30. Shift to Neutral, stab the gas pedal to the floor quickly a couple of times. Then shift back to drive. Then see if it shift normal.

there should be two bolts/nut that hold the master cylinder.
look under the dash on top of the clutch pedal

loose selector rod or its worn & binding up
Check and adjust

Change modulator valve on transmission.

Has anyone tried lubricating & or adjusting linkages/cable?

If you are going to just replace the valve body then there is no need to remove the transmission. All other repairs will require removal of the transmission from the vehicle.

first of all your truck is already in first gear when your going down the road....lol