Welcome to the forum! 
Note that I’ve moved your topic to the proper category as droidcam is an Arch User Repository (AUR) package.
Screenshots are normally not appropriate. They make the forum database backup larger and the text cannot be indexed by search engines to help others.
At the very least, please use words to describe what the screenshots are supposed to be telling us.
The only package that is applicable is the kernel headers as you presumably installed v4l2loopback-dkms.
There is no reason to manually install gcc or make as they’re part of the base-devel meta package required for using the Arch User Repository (AUR).
To correct the proper installation of the above packages since you most likely installed all of them explicitly:
Since linux-headers is an optional dependency of dkms and the other two are depdendencies of base-devel, set them as depdencencies:
sudo pacman -D --asdeps linux69-headers gcc make
Install base-devel so you have all the tools necessary for using the AUR:
sudo pacman -S base-devel
Please see: