public IReadOnlyList<ValueTuple<string,List<string>>> GetAvailableFonts()

{
    //returns a tuple per font: (string fontName, List<string> fontStyles)
    var fonts = SymbolFactory.Instance.GetAvailableFonts();
    foreach (var font in fonts)
    {
        var styles = string.Join(",", font.fontStyles);
        System.Diagnostics.Debug.WriteLine($"{font.fontName}, styles: {styles}");
    }
}

{
    //Note: Needs QueuedTask to run
    //using the default font
    var textSym1 = SymbolFactory.Instance.ConstructTextSymbol();
    var textSym2 = SymbolFactory.Instance.ConstructTextSymbol(
                       ColorFactory.Instance.BlueRGB, 14);

    //using a specific font
    var textSym3 = SymbolFactory.Instance.ConstructTextSymbol("Arial");
    var textSym4 = SymbolFactory.Instance.ConstructTextSymbol(
                      "Arial", "Narrow Bold");

    //or query available fonts to ensure the font is there
    var all_fonts = SymbolFactory.Instance.GetAvailableFonts();
    var font = all_fonts.FirstOrDefault(f => f.fontName == "Arial");
    if (!string.IsNullOrEmpty(font.fontName))
    {
        var textSym5 = SymbolFactory.Instance.ConstructTextSymbol(font.fontName);
        //or with a font+style
        var textSym6 = SymbolFactory.Instance.ConstructTextSymbol(
                                        font.fontName, font.fontStyles.First());
    }

    //overloads - font + color and size, etc
    var textSym7 = SymbolFactory.Instance.ConstructTextSymbol(
                    ColorFactory.Instance.BlueRGB, 14, "Times New Roman", "Italic");

    //custom symbol - black stroke, red fill
    var poly_symbol = SymbolFactory.Instance.ConstructPolygonSymbol(
      SymbolFactory.Instance.ConstructSolidFill(ColorFactory.Instance.RedRGB),
      SymbolFactory.Instance.ConstructStroke(ColorFactory.Instance.BlackRGB, 1));
    var textSym8 = SymbolFactory.Instance.ConstructTextSymbol(
            poly_symbol, 14, "Georgia", "Bold");
}