Run this command:
sudo nano /etc/dhcpcd.conf
At the bottom of that file enter the information you want for eth0 or wlan0
interface eth0
static ip_address=192.168.1.99
interface wlan0
static ip_address=192.168.1.100
static routers=192.168.1.1
static domain_name_servers=202.62.64.3 8.8.8.8
References:https://www.electronicshub.org/setup-static-ip-address-raspberry-pi/