The STL should be available on all the files you were asking for. Click the drop down arrow on the right side of the download button and choose "download STL"
If you are using BambuSlicer or OrcaSlicer, make sure you have two colors selected, then after you add the text, click "objects" on the left, there should be a number icon on the right of the text line, change it to the corresponding color, then slice. Hope this helps!