Preview:
/* CODE FOR DEMONSTRATION PURPOSES */
function setFontAndBackgroundColorCell() {
  var ss = SpreadsheetApp.getActiveSpreadsheet();
  var sheet = ss.getSheets()[0];
  var cell = sheet.getRange('B2');
  cell.setFontColor('yellow');
  cell.setBackground('red');
  cell.setValue('TEST');
}
/* CODE FOR DEMONSTRATION PURPOSES */
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