ApacheHTTPServer configuration problems

I am a beginner in php when I configure ApacheHTTPServer. today, when I configure ApacheHTTPserver, I find that the software installation is completely normal. but when I open the browser, enter http: // localhost/, the input address is displayed on the window of the world. ApacheHttpServer is started and successful. Apache HTTP Server Configuration
I am a beginner in php. today, when I configure Apache HTTP server, I find that the software is completely correct when I install it. but when I open the browser and input http: // localhost, the input address is incorrect on the window of the world. Apache Http Server is started and successful. The web page cannot be opened. I changed several Apache versions.
In addition, I encountered a problem during the configuration of MySQL. in the last step, I always prompted that the service could not be created ,,, all my configurations are done according to what I have mentioned in the book.

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I don't know what books you are referring.
Varies depending on the personal computer configuration.
Installing Apache may sometimes conflict with other service software, such as IIS. you can set the service port by yourself.
If a problem occurs during mysql installation, you can uninstall and reinstall it. you need to delete the original folder completely or it will not be used.
What are the common problems in the process? what are the Chinese options? skip registration?