Will Ola's default IndexOptimizer job update my stats?
By default, the script does not perform statistics maintenance. The documentation for the script's parameters can be found here.

Value   Description
================================
ALL     Update index and column statistics.
INDEX   Update index statistics.
COLUMNS Update column statistics.
NULL    Do not perform statistics maintenance. This is the default.


So if you let the main script create your maintenance jobs for you, and you wanted to update index and column statistics, then you'd need to edit the IndexOptimize job and add , @UpdateStatistics='ALL' into the procedure call.