Firmwear fiasco with ender 3 vs code and SKR 1.4 (no replies)

Hello I hope you can help here. I have a Ender 3 Pro and a SKR 1.4 Turbo I'm trying to install into my printer. BUT every time I compile in vs CODE I get the error shown in the picture. ALWAYS Even with downloading "fresh" files to use. This has been going on 3 weeks till I came here to RepRap. I hope someone can tell me what I'm doing wrong. I have no experience with firm wear. Oh and also thers a red squiggle and a yellow "light bulb" top of configuration_adv.h

specs

Marlin 2.0
vs CODE 1.65.2

Ender 3 pro ( i installed a Ender Extender 300XL kit that makes bed 300mm x300mm and z 390mm. I haven't mentioned that at all yet in firm wear)
SKR 1.4 Turbo, TMC 2209 stepper drivers, DCDC thingy, and following I haven't installed till printer up and running a while, WIFI, BTT writer.
Dual Z stepper motors \
120volt 750 watt SSR controlled bed heater


Is there a book " firm wear for dummies"?