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
sudo apt install libmikmod-dev libfishsound1-dev libsmpeg-dev liboggz2-dev libflac-dev libfluidsynth-dev libsdl2-mixer-dev libsdl2-mixer-2.0-0 -y;
#install sdl true type fonts - if you want to use text
sudo apt install libfreetype6-dev libsdl2-ttf-dev libsdl2-ttf-2.0-0 -y;