Adobe Premiere Pro - Adjusting Audio and Pan with Keyframing

Select track in timeline

*If you need delete the track and replace, just select the track and press delete on your keyboard

Go to effects panel

Click on the Level drop down to change volume

You can control the volume over time in a clip. In other words, you can have the volume increase and decrease as the clip plays. 

Do any of the following:

• Enter a value for the level. A negative value decreases the volume level and a positive value increases the volume level. A value of 0.0 represents the original clip’s volume level without adjustment.
• Click the triangle next to Level to expand the effect options, and then use the slider to adjust the volume level.

A keyframe is automatically created at the beginning of the clip’s timeline in the Effect Controls panel.

To use keyframes to fade the sound in, create two keyframes: one for the start and one for the peak volume you want the fade to reach.

Then, in the timeline, select the first keyframe and drop down.

To change the volume for the entire track globally, make sure the stopwatch to the left of Level is not blue. Then alter the value.

Beware if you have already created keyframes, selecting the stopwatch would erase all this previous information

To change the pan, in the Effect Controls tab, click the drop down arrow to the left of Panner. Here you can alter the levels and add keyframes similarly to the Levels tab.