By IUPAC nomenclature,

The parent chain in this compound is the cyclohexane ring, which consists of six carbon atoms.

The substituents are:

Ethyl group  attached to third carbon.

Two methyl groups  attached to carbon $1$ .

The Numbering must be given the carbons in the cyclohexane ring so that  the substituents get the lowest numbers,

Hence, the name is $3$-ethyl $1, 1$-dimethylcyclohexane