The question is vague but here is a bit of a guess.

A few tips to start with:

• You probably don't need axios for most front-end solutions. It is just an extra dependency. Use the fetch API instead.
• Keep your variable names consistent - setCountryName instead of setcountryName.
• The useMemo hook will prevent a function from being created on every render. You can pass the second argument of a dependency array that contains variables. If any of those variables change, useMemo will recalculate that function.

Now to the code. You can give useEffect the second argument of an array of variables. If any of these variables change, the effect will run the callback function provided as the first arg. useEffect will also always run once when the component mounts.

Create a second effect that runs when you get the data needed to make the weather API call.

All things above considered, your code might now look like this (untested):

import { useState, useEffect } from 'react';
require('dotenv').config();

function IpGet() {
    const [ip, setIP] = useState('');
    const [countryName, setCountryName] = useState('');
    const [cityName, setCityName] = useState('');
    const [countryCode, setCountryCode] = useState('');
    const [countryStateName, setCountryStateName] = useState('');

    const weatherKey = process.env.REACT_APP_WEATHERKEY;

    // useMemo to avoid recreating this function on every render
    const getData = React.useMemo(() => async () => {
        const res = await fetch('https://geolocation-db.com/json/');
        setIP(res.data.IPv4);
        setCountryName(res.data.country_name);
        setCityName(res.data.city);
        setCountryCode(res.data.country_code);
        setCountryStateName(res.data.state);
    });

    const getWeather = React.useMemo(() => async () => {
        if (!cityName || !countryStateName || !weatherKey) return;

        const weatherUrl = `https://api.openweathermap.org/data/2.5/weather?q=${cityName},${countryStateName}&appid=${weatherKey}`;
        const weatherData = await fetch(weatherUrl);

        // Do something with weatherData here... set to some state or something.
    });

    useEffect(() => {
        getData();
    }); // No dependency array, so this will only run once when the component mounts

    useEffect(() => {
        getWeather();
    }, [cityName, countryStateName]); // This will trigger the callback when any of these variables change.

    return (
        <div className='IpGet'>
            <h4>{ip}</h4>
            <h4>{countryName}</h4>
            <h4>{countryCode}</h4>
            <h4>{countryStateName}</h4>
            <h4>{cityName}</h4>
        </div>
    );
}

export default IpGet;