How to using library (header files) from another package c++

Hello i just trying to make a c++ program, the program includes a header files from another package.
my case:
i have 2 packages. the package 1 is file that i want to program with and package 2 included the library that i want to use.
I have tried to use #include "package2/headerThatIWantToUse.h"
it compiles no error but i can’t access the api/function on that library.

I know it must edit the CMakeLists and package xml on package 1 right? what needs to be edited?
And how can i use #include "headerThatIWantToUse.h" (without writing "package2/") ?

Hi @billy.nugraha.s,

Assuming package2 is properly built and working, you just need to add it as a dependency when creating package1 in addition to importing the header file. E.g

catkin_create_pkg package_1 roscpp package2

You need to write package2 as part of the include.