CMake project setup with subdirectories

I'm struggling with setting up CMake to support proper include paths.

I have a repository in this format:

root/
├── src/
│   ├── helpers/
│   │   ├── helper.h
│   │   ├── helper.cpp
│   │   └── CMakeLists.txt
│   ├── logger.h
│   ├── logger.cpp
│   ├── main.cpp
│   └── CMakeLists.txt
└── CMakeLists.txt

(I'm new to CMake and haven't made larger-sized C/C++ projects before, so this may not be a good way to organize things).

I am trying to setup CMake to create an executable from this project. I am able to compile everything properly; however, I'd like to be able to include things using paths relative to a path in the list of include directories.

For example, in my helper.h, I have #include "../logger.h" but I would like to be able to write #include <myproject/logger.h> instead (or something of the sort).

Here is my top level CMakeLists.txt:

cmake_minimum_required(VERSION 3.14)
project(
    myproject
    VERSION 1.0.0
    LANGUAGES CXX C
)

add_executable(${PROJECT_NAME})

add_subdirectory(src)

Here is my src/CMakeLists.txt:

cmake_minimum_required(VERSION 3.14)

target_sources(${PROJECT_NAME} PRIVATE 
    main.cpp
    logger.cpp
)

add_subdirectory(helpers)

And here is my src/helpers/CMakeLists.txt:

cmake_minimum_required(VERSION 3.14)

target_sources(${PROJECT_NAME} PRIVATE 
    helper.cpp
)

I thought of adding target_include_directories to each level for their current directory but that did not change anything.

(Also, let me know if there are better ways to setup the project as a whole).