There are 4 different shapes on ROBLOX studio, first off is the block, every one mostly uses this for basic building or other parts it's 6 sided 3D shape that can be formed into any size, the second shape is a sphere it can be any size and any color, the third shape is a cylinder you can change the size,color,malarial,etc, and the last shape is a weld and it has a ramp feature that you can use it for advance building, ramps, etc, To summon any of these shapes into your workspace,game,place,etc, all you need to do is right click and click "insert part", or go to shapes and click the shape you want.
Now, lets get creative, to change color of your shape go to the "Model" section and click the color area then you get a whole list of different shades of colors, now lets get even bigger if you want to change the size go to to the re-size section and you get 6 mini-spheres in 3 different colors (Red, blue, and green) each one has a different role (Width, height, and length), now materiel, if you want to change the materiel go to the section called "Materiel" click it and you get a list of these;
This is not what you exactly see on the list you just see a basic list of these materials, but this picture has some missing materiel but those have been advanced into a feature you would like after I explain the "Transform" tool, it is all the tools into one but with a scale to measure the height, width, and length.
Now for extreme advanced building, Unions, unions are objects that are fused with 2 different parts fused together 1 normal