How can I rotate a whole model?
Have a primary CFrame within the model properties and if I think correctly just rotate that part and it should rotate the whole model.
The way I like to move my models around is using SetPrimaryPartCFrame, to set the PrimaryPart of a model, simply select the model and in the Data for that model you should see where it says "PrimaryPart" and once you click on that you can select what part you want to be the PrimaryPart for that whole entire model, once you have selected a part to be the PrimaryPart you can use SetPrimaryPartCFrame to move or rotate the model. If you already have your PrimaryPart chosen then an example on how exactly to use it would be
game.Workspace.Model:SetPrimaryPartCFrame(CFrame.new(0, 0, 0))