Select the days for delivery from the weekdays listed under this Available days option.
There are multiple places to find settings for different settings like:
The Available Days option is available in the Product Calendar add-on.
In Global Product Settings
Product Calendar > Global Settings > General Settings > Available Days
In Single Product Settings
Product Calendar > Product Settings > Add button right to the product name > Available Days
Locations > Edit store location > Store Pickup tab > Available Days
Locations > Edit store location > Local Delivery tab > Available Days