1. Para quem está tendo dificuldade com requisições AJAX para coletar alguns dados da API com método POST ou GET.
2. Documentação AJAX: https://www.w3schools.com/js/js_ajax_intro.asp
3. Codigo GitHub: https://github.com/lipeomiguel/AluraTools/blob/main/Doc/js/Tools/Ajax/ajaxResquest.js

• CODIGO:

function xmlRequest(method='GET',url='https://api.ipify.org?format=json',asyncCallback=true,callback=false){
  this.method = method;
  this.url = url;
  this.asyncCallback = asyncCallback;
  this.callback = callback;
  this.return = (callback)=>{
      /**
        * ! Check if the callback is being called!
        * ? ajax.return(?);
      **/
      const xml = new XMLHttpRequest();
      xml.open(this.method,this.url,this.asyncCallback);
      xml.send();
      xml.onreadystatechange = ()=>{
        if(xml.readyState == 4){
          callback(xml);
      }
    }
  }
}
const ajax = new xmlRequest();
ajax.return(dados); //? Create callback for data processing: [ ajax.return(a); ] 
function dados(xml){
  console.log(xml.responseText);
}

• VSCODE SNIPPETS:

"JS AJAX RESQUEST [ GET | POST ]": {
        "prefix": "JSAJAXRESQUEST",
        "body": [
            "function xmlRequest(method='GET',url='https://api.ipify.org?format=json',asyncCallback=true,callback=false){",
            "	this.method = method;",
            "	this.url = url;",
            "	this.asyncCallback = asyncCallback;",
            "	this.callback = callback;",
            "	this.return = (callback)=>{",
            "			/**",
            "				* ! Check if the callback is being called!",
            "				* ? ajax.return(?);",
            "			**/",
            "			const xml = new XMLHttpRequest();",
            "			xml.open(this.method,this.url,this.asyncCallback);",
            "			xml.send();",
            "			xml.onreadystatechange = ()=>{",
            "				if(xml.readyState == 4){",
            "					callback(xml);",
            "			}",
            "		}",
            "	}",
            "}",
            "const ajax = new xmlRequest();",
            "ajax.return($1); //? Create callback for data processing: [ ajax.return(a); ] ",
        ],
        "description": "This AJAX function is used to make simple requests like GET or POST.",
    }

3. ATENÇÃO: SOLICITAÇÕES COM ENVIO DE PARÂMETROS DE HEADER, É NECESSÁRIO TER A DOCUMENTAÇÃO E FAZER ALTERAÇÕES NO CÓDIGO.