A blindfold is a piece of cloth that someone else ties over your eyes so you can't see. People are often blindfolded so they can be lead to a surprise without knowing where they are going. Some games require you to be blindfolded, like pin the tail on the donkey. The person in the picture is playing a video game blindfolded.
Scientific name: Au
Gold is a heavy, soft, yellow metal that is easy to work with. It is the softest metal, and is very dense, much denser than lead.
Gold is very stable and is used to coat other more reactive metals to protect them, but its primary use is in jewelery. Pure gold is too soft to make jewelery out of, and is usually mixed with silver, copper and other metals.
You hold something when it is securely in your hands. You might also hold something by supporting it, for example "that post is holding the roof up".
Scientific name: genus: tagetes
A mold is a hollow form. When you fill up a mold with something like molten metal or plaster, let it set and then remove the mold, you have a solid shape that matches the shape of the inside of the mold.
Mold is also an alternative spelling for mould.
The mold in the picture is for a small bridal statue of a bride and groom.