I try to find some development codes such as config.h, but I could not find them in my Wireshark folder.
The binary packages we supply for Windows and macOS do not include the source, and operating systems that include Wireshark as a package (Linux distributions, the *BSDs, etc.) generally don't provide the source in a binary package. (Build-from-source distributions such as Gentoo may be an exception.)
To get the source, either:
- get it from our GitLab repository, as suggested by @grahamb;
- download the source code for the release from the "Source Code" link on our download page, if your Wireshark was downloaded from our Web site;
- install the source package if your Wireshark came from a binary package provided by your operating system (those operating systems should provide a source package of some sort).