What is the IUPAC name for (CH3)3COH?

It's 2-methylpropan-2-ol (also known as "tertiary butanol": tert-butanol)

I think that there is some thing wrong with the formula. I hope that you are asking (CH3)3 -COH. All the three methyl groups are attached to the same carbon atom which is also linked to one -OH group.