The similarities of hydrogen to metals can be provided as follows:Electronic configuration: Like all the other elements Hydrogen will consist of one electron in its shell.Noble gas configuration: Just like alkali metals there is a need to lose one electron in its valence shell to achieve a stable configuration as that of the next noble gas which will be Helium. It will hence form a proton ion.Good reducing agent: Hydrogen is one of the reducing agents that are widely used just like other alkali metals.Forms halides: Just like alkali metals the hydrogen will combine with electronegative elements to form halides.