what do they do being the second type?
They have medical applications, can be used in insecticides and herbicides, also they have antiseptic, antifungal, and antiviral properties.
Metalloid
All six of the elements commonly recognised as metalloids have toxic, dietary or medicinal properties. Arsenic and antimony compounds are especially toxic; boron, silicon, and possibly arsenic, are essential trace elements. Boron, silicon, arsenic, and antimony have medical applications, and germanium and tellurium are thought to have potential.
what is the basis of arranging the elements in the modern periodic table Atomic number, electron configuration, and recurring chemical properties. what is the purpose of the table? UNANSWERABLE why is called so? Because of the tabular display of the chemical elements. what sorts of elements can we see in it? Nonmetallic elements such as metalloids,  groups of families of elements and elements having metallic lustre. can you name a few of the first form? Boron, silicon, germanium, arsenic, antimony, and tellurium. where are they commonly applied? Alloying components, biological agents, catalysts and flame retardants.
wiki:8264393
Metalloid [SEP] Biological agents
All six of the elements commonly recognised as metalloids have toxic, dietary or medicinal properties. Arsenic and antimony compounds are especially toxic; boron, silicon, and possibly arsenic, are essential trace elements. Boron, silicon, arsenic, and antimony have medical applications, and germanium and tellurium are thought to have potential. Boron is used in insecticides and herbicides. It is an essential trace element. As boric acid, it has antiseptic, antifungal, and antiviral properties. Silicon is present in silatrane, a highly toxic rodenticide. Long-term inhalation of silica dust causes silicosis, a fatal disease of the lungs. Silicon is an essential trace element. Silicone gel can be applied to badly burned patients to reduce scarring.