Answer
The IUPAC name of the compound is $3-methylbutan-1-ol$. Its common name is $isopentyl \hspace1mm alcohol$.
Work Step by Step
The compound has 4 carbon atoms in its longest chain containing the alcohol group. It has a $methyl$ substituent at position 3 and the alcohol group at position 1. So, the IUPAC name of the compound is $3-methylbutan-1-ol$. Its common name is $isopentyl \hspace1mm alcohol$.