I wouldn't recommend uploading static binaries and header files to GitHub. A better approach might be to create a script that is executed before compilation that downloads these dependencies. Alternatively, you could use what is already installed on the machine, if that is applicable.
If you choose to upload the external libraries to GitHub, you must comply with all of the terms and conditions of their licenses. For example, you must show the full copyright notice for some of these libraries.
https://github.com/nigels-com/glew/blob/master/LICENSE.txt
https://www.libsdl.org/license.php
http://glm.g-truc.net/copying.txt
It looks like the licenses for your external dependencies are fairly permissive. However, I'll give you an example of might happen if you chose to upload a GPLv3 binary. If you uploaded a GPLv2 binary, you would be required to provide the source code for this binary as well as all instructions to configure, compile, and install the binary. If you don't comply with these requirements, you could lose your rights to continue using the binary or be sued.
Do I have to credit them somewhere, just let the user manually install them or is there something that I'm missing?
Yes, the external libraries you are using require attribution if you choose to upload static binaries to GitHub. See the URLs to the licenses that I linked above. From the MIT license:
The above copyright notice and this permission notice shall be included in
all copies or substantial portions of the Software.
I don't believe you have to do any sort of attribution if you let the user manually install the dependencies. However, the same sort of attribution would be required if you are statically linking your these libraries into your program, and sending the resulting binary to somebody else.
