Map<String, Object> m = (Map<String, Object>) JSON.deserializeUntyped('Hello World');
HttpRequest req = new HttpRequest();
//String textToTranslate = EncodingUtil.urlEncode((string)m.get('TextBody'), 'UTF-8');
//String textToTranslate1 = EncodingUtil.urlEncode((string)m.get('Subject'), 'UTF-8');
String textToTranslate = EncodingUtil.urlEncode('Hello World', 'UTF-8');
String textToTranslate1 = EncodingUtil.urlEncode('I am translation', 'UTF-8');
String targetLangCode = 'German';
req.setEndpoint('callout:GoogleTranslationApi');
req.setMethod('POST');
String Body ='key='+'{!$Credential.Password}'+'&q='+textToTranslate+'&target='+targetLangCode+'&format=text'+'&q='+textToTranslate1+'&target='+targetLangCode+'&format=text';
req.setBody(Body);
System.debug('Hey this is Body of getTranslatedResponse-->'+ Body);
HttpResponse res = new Http().send(req);
System.debug('-->'+ res.getBody());
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