How do I get XTest.h on Ubuntu System? [duplicate]

I am having issues compiling a project. I believe I need to include the XTest.h file but I don't have in my X11 directory.

This is a side project to help me learn how to manage dependencies, build, compile and troubleshoot errors.

g++ -L robot-master/Binaries/Linux/libRobot.a main.cpp -lRobot -lX11/usr/bin/ld: /usr/lib/gcc/x86_64-linux-gnu/11/../../../../lib/libRobot.so: undefined reference to `XTestQueryExtension'/usr/bin/ld: /usr/lib/gcc/x86_64-linux-gnu/11/../../../../lib/libRobot.so: undefined reference to `XineramaQueryScreens'/usr/bin/ld: /usr/lib/gcc/x86_64-linux-gnu/11/../../../../lib/libRobot.so: undefined reference to `XineramaIsActive'/usr/bin/ld: /usr/lib/gcc/x86_64-linux-gnu/11/../../../../lib/libRobot.so: undefined reference to `XTestFakeButtonEvent'/usr/bin/ld: /usr/lib/gcc/x86_64-linux-gnu/11/../../../../lib/libRobot.so: undefined reference to `XTestFakeKeyEvent'/usr/bin/ld: /usr/lib/gcc/x86_64-linux-gnu/11/../../../../lib/libRobot.so: undefined reference to `XTestGrabControl'/usr/bin/ld: /usr/lib/gcc/x86_64-linux-gnu/11/../../../../lib/libRobot.so: undefined reference to `XineramaQueryVersion'collect2: error: ld returned 1 exit status

XTest.h

sudo apt-get install libxtst-devReading package lists... DoneBuilding dependency tree... DoneReading state information... Donelibxtst-dev is already the newest version (2:1.2.3-1build4).The following packages were automatically installed and are no longer required:  libwpe-1.0-1 libwpebackend-fdo-1.0-1Use 'sudo apt autoremove' to remove them.0 upgraded, 0 newly installed, 0 to remove and 3 not upgraded.

Recommended libraries for package installs

sudo apt-get install libxt-dev libxtst-dev libxinerama-dev -yReading package lists... DoneBuilding dependency tree... DoneReading state information... Donelibxinerama-dev is already the newest version (2:1.1.4-3).libxt-dev is already the newest version (1:1.2.1-1).libxtst-dev is already the newest version (2:1.2.3-1build4).The following packages were automatically installed and are no longer required:  libwpe-1.0-1 libwpebackend-fdo-1.0-1Use 'sudo apt autoremove' to remove them.0 upgraded, 0 newly installed, 0 to remove and 3 not upgraded.