I have drawn a hexagon using the shape tool, and now I want to draw a star inside it. When I draw the star, the hexagon goes away. Does this have something do with the vector mask? When I try doing the same thing in a new (transparent) layer, the same thing happens. Help! :)
A shape can be invisible for several reasons
- no stroke nor fill and isn't selected
- fully below another bigger shape with opaque fill
- isn't hidden, but has exactly the same color as the bigger shape below
Maybe it's useful to learn the tool options. There are plenty of them and the result is very different with different options. Also Layers panel, Paths panel and all path editing tools are essential.
Few rudimentary explanations (sorry for using legacy Photoshop)
Draw a vector shape. It's actually a mask (=vector mask) for a layer and defines the visible part of a layer. It's an editable path, which makes it different than normal layer masks (=bitmaps). You can define the fill color of the layer and the generated shape. Its the green rectangle in the screenshot.
Draw a new work path or modify an existing path, which is selected in the Paths panel. Paths can be used for selections and they can be stroked, but they have no bitmap layer content.
Fill an area with the foreground color in a bitmap layer which is selected in the Layers panel
4...8. These define how the new path or vector mask is combined with the selected old one. Available options vary depending on what is selected in the panels or are you going to draw a new vector mask or a new path. Options 1 and 4 together force the new shape to be a new vector mask for a new layer.
These short explanations hopefully show that the richness of possible combinations cannot be explained shortly. Right clicks with the mouse reveal much more possiblities. For editing the shapes there are plenty of tools in the Toolbox and Layer > Layer style -effects are applicable.
Search for tutorials, see the original Adobe documentation and practice. Otherwise your time is wasted with unpredictable results.