On the same LAN, how smart devices access the interface to the PC-side TP

The device and computer are in the same network segment, and an existing smart device requires access to the Thinkphp interface.
Normal access to this interface on the computer is:
http://localhost/demo/index.php/C/A
Or:
http://127.0.0.1/demo/index.php/C/A
So how can smart devices access the interface?
An attempt was made to access the IP, but it will appear: You do not have the permission to access in this server.
Modified Apache Httpd.config File:

< Directory / >     Options FollowSymLinks     AllowOverride None     Order deny,allow     Deny from all< /Directory >

Still does not have permissions. Does it have anything to do with firewalls?
Or if you use a computer to broadcast WiFi, so that the device connected to the WiFi, there will be no such situation?

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