In order to change the IP address of the Raspberry PI you have to find the configuration network file. It is located in /etc/network/interfaces. To edit this file you can use nano, the default editor available in the official Raspberry PI OS, Raspbian.
sudo nano /etc/network/interfaces
From here, if you use an Ethernet cable you can modify the lines below “allow-hotplug eth0”
Static IP address
To change the IP address of the Raspberry PI with a static one (i.e 192.168.0.14), you have to know your netmask and gateway.
allow-hotplug eth0 iface eth0 inet static address 192.168.0.14 netmask 255.255.255.0 gateway 192.168.0.1
Those IPs are fictives and need to be replaced by the one of your current configuration.
How to get the netmask and gateway ?
On Windows you can use the shortcut Win+R. Then you can type “cmd” and “ipconfig”. See the video
On Mac or Linux, open the terminal and type “ifconfig”.
Automatic IP address (DHCP)
To use the DHCP protocol (IP address are automatically delivered by the router or switch), you can just replace “static” or “manual” by “dhcp”. No need to specify the netmask and gateway because DHCP delivered them by definition.
allow-hotplug eth0 iface eth0 inet dhcp
And for the WIFI ?
You just need to replace “eth0” by “wlan0” and that’s it!