Edit in JSFiddle

Survey.Survey.cssType = "bootstrap";

var json = {
    "elements": [
        {
            "type": "tagbox",
            "isRequired": true,
            "choicesByUrl": {
                "url": "https://restcountries.eu/rest/v1/all"
            },
            "name": "countries",
            "title": "Please select all countries you have been for the last 3 years."
        }
    ]
};

window.survey = new Survey.Model(json);

survey
    .onComplete
    .add(function (result) {
        document
            .querySelector('#surveyResult')
            .innerHTML = "result: " + JSON.stringify(result.data);
    });

survey.data = {
    countries: ['France']
};

$("#surveyElement").Survey({model: survey});
<div id="surveyElement"></div>

<div id="result"></div>