I would like to have a column where I can see date of first page hit by contact and calculate how many days after it this contact make a reservation. How can I do this?
You need modifications to Mautic in order to do this.
The report doesn’t allow you to do calculations in a ways, that is required to do this.
Could you tell me what kind of modifications?
You need to change the reporting system in Mautic and add new options, like calculated columns.
A workaround would be to use a third party app, like Metabase or Google Looker.
Here is a tutorial: