The PHP default website opens and appears E:\phpStudy\WWW\index.php on line 1

Question

Please tell me what does it mean when opening the website and displaying Fatal error: Call to undefined function get_header() in E:\phpStudy\WWW\index.php on line 1

Answer 1

The function is undefined. If you look at the prompt, it says that there is a get_header() function in the first line!