How to change loudness adjustments professionally?

You have been given several simple solutions. I think it’s kind of sad that you seem to think that you are going to become proficient in such a deep program in a few days and because you haven’t spent the time to learn the software that you then blame the DAW. I think you will find that every DAW has a deep learning curve if you want to really become good with it.

I think the easiest would be to just automate the volume of your individual tracks and copy the volume automation curve to the other tracks. This is something that you as a beginner should know how to do-it’s a basic thing that you’ll need to do 100 times a day. If you don’t know how to do it, then don’t complain about the software, and spend a few minutes working on learning it-or ask a specific question.

EDIT: It sounds now like you are just asking about a global volume control. That is your master output. Click the “W” and wiggle the output fader. Now you can draw the automation curve for master volume.