From onlinetuition

1. NAMING ALCOHOLS
1.All alcohol members have a suffix 'ol'. For example,
methanol, ethanol, propanol ......
2.The nomenclature of alcohol, like alkanes, is based on
the number of carbon atoms in the molecule, but the 'e'
in the nomenclature of alkanes is replaced with the
suffix 'ol'. Example, ethane (alkane) becomes ethanol
(alcohol)
3.The positions of the alkyl and hydroxyl groups that the
attached to the carbon chain are shown by numbering
the carbon atoms. The hydroxyl group must always get
the smallest possible number.
Example 1
(Propan-2-ol)
Longest chain: 3 carbon (propanol)
Position of hydroxyl group: 2
Alkyl: -

2. Example 2
(Pentan-1-ol)
Longest chain: 5 carbon (pentanol)
Position of hydroxyl group: 1
Alkyl: -
Example 3
(2-methylpropan-2-ol)
Longest chain: 3 carbon (propanol)
Position of hydroxyl group: at C2
Alkyl: Methyl at 2nd carbon

3. Example 4
(3-methylbutan-1-ol)
Longest chain: 4 carbon (butanol)
Position of hydroxyl group: at C1
Alkyl: Methyl at 3rd carbon
Example 5
(2,2-dimethylpropan-1-ol)
Longest chain: 3 carbon (propanol)
Position of hydroxyl group: At C1
Alkyl: 2 Methyl, both at 2nd carbon