#For this you will do use ln command like this
ln -s /mnt/d/projects/web-project /var/www/web-project
#Just a tip for developers who would work in Windows and would like to access those files in Linux Subsystem real quick. You can use symbolic links.
#For example If you are working on a project in d:/projects/web-project, you can create a symlink at location /var/www/web-project and all the files you change in windows will be readily available to be accessed in Linux Bash.
#In above line /mnt/d was meant to be your d drive on windows. Setup your Apache virtual host to this path and you are ready to go.