You can do that in Affinity Designer’s appearance panel as well. Here is a video tutorial showing how.
However, I noticed that Affinity Designer’s appearance panel is more finicky than Adobe Illustrator’s. Affinity Designer will only allow you to add multiple fills and strokes to a single object and not live text. So, you will have to convert your text to curves, then ungroup it, then use pathfinder to make your text all one “shape” and then apply multiple fills and strokes. The nice thing about Affinity Designer is they allow strokes to have a fill of “erase” which knocks out of any background, including the strokes behind it.
I would also recommend keeping a version of your logo that is editable text as well, just in case.