As @Jules said, you need to do a union to ensure that the paths are all connected as an outline.
The group function just puts together separate objects for simultaneous selection and operation. The combine function takes paths and unites them into one object. But the union function joins the paths in particular ways.
The design you posted is a group of eleven objects. It is filled, so that means it’s going to be engraved.
As it is, this design will need some work if you want to cut it out as a stencil and not have separate parts. Assuming that you want to cut it as a stencil. A union just won’t work as is.
For example, your lines above and below “Hutton” are actually single lines.
You’ll want to remove the fill and define the stroke. I usually use .25 pixels. Another way of checking to see that your lines are correct for cutting an outline that won’t have drop outs is to change to Outline view. Here you can see the distinct lines and how they would overlap and cause issues.
It’s almost there. You just have to work on the circle around the “H” and make those two lines long thin boxes. Then you can join things.
I think this is what you are looking for. This is the SVG file.
Here is a screenshot for those who want to see more easily the result.