Before I bought an Ender 3 PRO, I was using a Wanhao i3 plus, Wanhao was ejecting filament before the start of the print, I mean it is going to the left corner edge and was pushing like 5-10 mm filament to clean nozzle or release the pressure, as far as I understand, the Ender 3 doesn't do that, how can I make the Ender 3 to do same thing with G-code?

I'm asking this because the nozzle is allready heated while BLTouch is executing G29, so the extruder motor is not moving but the filament is leaking from nozzle due to temprature, until the BLTouch finishes the G29, it creates a long string, when the printer is starting to print, it prints a straight line between front & rear left corner, while printer printing a line that produces a string sticking to the nozzle and kills the print (most of the time that string catches the first layers).

I thought, maybe if I can force the printer to eject filament before starting to print like the Wanhao does, I could fix this problem?

I think this code does that line;

G1 X0.1 Y200.0 Z0.3 F1500.0 E15 ; Draw the first line

I would like to modify this line, but I'm relatively new to modifying G-code.