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/