How to get an user ID from username?

I would like to know how I can send a request via ROBLOX's User API but it seems that is not specifically documented. I am making a log in site via status and I need the ID to get the users status. I appreciate any help given.

If I absolutely need to use /v1/user/search, I want to get the id of the first user.

You need to simply make a fetch request and get the User ID from the URL.

function getUserID(name)
{
    return new Promise((res, rej) => {
        fetch(`https://www.roblox.com/users/profile?username=${name}`)
            .then(r => {
                // check to see if URL is invalid.
                if (!r.ok) { throw "Invalid response"; }
                // return the only digits in the URL "the User ID"
                return r.url.match(/\d+/)[0];
            })
            .then(id =>{
                // this is where you get your ID
                console.log(id);
            })
    })
}

// without Promise

function getUserID(name)
{
    fetch(`https://www.roblox.com/users/profile?username=${name}`)
        .then(r => {
            if (!r.ok) { throw "Invalid response"; }
            return r.url.match(/\d+/)[0];
        })
        .then(id => {
            console.log(id);
        })
}

Sorry I'm new to posting answers on StackOverflow. If you need any help feel free to ask.