After you complete the FTP test, you are going to take 95% of the power output value and plug it into your training app, such as the SRAM AXS app. This number is going to give you an established baseline for where your power output should be in order to meet your training goals.
Congratulations! You are now ready to start training with a power meter. You are well on the way to improving your cycling technique, getting stronger legs, and improving cycling speed and endurance.