nerode equivalence classes q - prefix?
There are three equivalence classes, and this can be seen from the minimal DFA, which has three states. The equivalence classes are $\epsilon,0\Sigma^*,1\Sigma^*$. Indeed:


$\epsilon$ and $0$ are in different classes since $\epsilon 1 \in L$ whereas $01 \notin L$.
$\epsilon$ and $1$ are in different classes since $\epsilon \epsilon \notin L$ and $1\epsilon \in L$.
$0$ and $1$ are in different classes since $0\epsilon \notin L$ whereas $1\epsilon \in L$.
All words in $\{\epsilon\}$ are clearly equivalent.
All words in $0\Sigma^*$ are equivalent since $wz \notin L$ for all words $w \in 0\Sigma^*$ and all words $z$.
All words in $1\Sigma^*$ are equivalent since $wz \in L$ for all words $w \in 1\Sigma^*$ and all words $z$.