I solved this situation in parts, I do not understand much of the subject, but I saw a video in English and I was able to take advantage of the subject.
First you enter the address: www.console.Developers.google.com/project/507871535838/apiui/Credential , logs in and generates a Key for browser applications, similar to this: AIzaSyAUdzBYnsoHcgeDqY9sflH0bv0XaIBjpsI you will use it in script.js
Then you download the file jquery-1.11.3.min.js and creates 2 files: index.html and script.js
In the index.html that you created, calls the files .js and to show the videos, you call through the code below in the body of index.
<ul id="results"></ul>
Now create the script.js:
var channelName = 'Aqui vai o nome do canal';
var vidWidth = 250; //largura de cada vídeos
var vidHeight = 187; //altura de cada vídeos
var vidResults = 10; //qtd de vídeos que vai aparecer na galeria max 50
$(document).ready(function(){
$.get(
    "https://www.googleapis.com/youtube/v3/channels",{
        part: 'contentDetails',
        forUsername: channelName,
        key: 'AIzaSyAUdzBYnsoHcgeDqY9sflH0bv0XaIBjpsI'},//altere para sua chave
        function(data){
            $.each(data.items, function(i, item){
                console.log(item);
                pid = item.contentDetails.relatedPlaylists.uploads;
                getVids(pid);
            })
        }
);
function getVids(pid){
    $.get(
        "https://www.googleapis.com/youtube/v3/playlistItems",{
            part: 'snippet',
            maxResults: vidResults,
            playlistId: pid,
            key: 'AIzaSyAUdzBYnsoHcgeDqY9sflH0bv0XaIBjpsI'},//altere para sua chave
            function(data){
                var output;
                $.each(data.items, function(i, item){
                    console.log(item);
                    videTitle = item.snippet.title;
                    videoId = item.snippet.resourceId.videoId;
                    output = '<li><iframe width="'+vidWidth+'" height="'+vidHeight+'" src=\"https://www.youtube.com/embed/'+videoId+'\"></iframe></li>';
                    //Append to resultes listStyleType
                    $('#results').append(output);
                })
            }
    );    
}
});
I hope I’ve helped, like I said, I’m a layman, but if anyone wants to get better, feel free.