What you need to do to install SDL is:
#install sdl2
sudo apt install libsdl2-dev libsdl2-2.0-0 -y;
#install sdl image - if you want to display images
sudo apt install libjpeg-dev libwebp-dev libtiff5-dev libsdl2-image-dev libsdl2-image-2.0-0 -y;
#install sdl mixer - if you want sound