This will require supports but I made it easy for you. I added a half circle at the bottom where the opening is, this is by design, its not needed for the model but it does block tree supports with touching buildplate option from filling the inside cavity, some will enter but are easily removed, or you can leave them inside, its up to you. The ones that enter are needed to make the print work. I also added blockers on the model, do not remove them or you will get a ton more interior supports. You can see it stuck on the buildplate in the photos.

Recommend outdoor material if planning on using outside. I sized this to be what I found online as a standard gnome size and can be printed on a normal sized printer.

PLA would work for shaded outdoor areas but why take the chance print in ASA, PETG, or ABS I suppose.

I printed this in Ataraxia Art old world gold PETG with a .6mm nozzle at .4mm layers with a .4mm initial layer, 2 walls and 3 top and bottom 15% infill with 15% overlap . Makes a strong print.

I recommend filling with sand, or BB's. Less chance of the dog running off with it or it getting blown around the yard.

Scaling - you could scale this, make sure to scale them both, I don't recommend that.