I'll go ahead and give you the advice you would get from any of the 3d printing subs. Check out techingtech on YouTube. He has a lot of detailed guides and a website with some excellent calibration tools( https://teachingtechyt.github.io/calibration.html). Another thing to keep in mind, if you think your bed is leveled and your bed leveling sensor is calibrated correctly, creality is notorious for having warped beds and your bl touch can only do so much to help with that. If you think that's your issue you can get a glass build plate or 3rd party build plate. Also, go with cura over creality's slicer 100%.