Can I see how many people visited my portal and where they gave up before booking?

Yes, you can. A portal is a normal website as far as visitor tracking goes, so it can be linked to the usual free analytics tools, and on top of that the booking side of the system keeps its own record of searches made and bookings completed. Between the two you can see how many people arrived, which pages they landed on, how many went as far as a search, and how many of those searches turned into a paid booking.

The part most owners find useful is the drop off. Because a booking moves through clear steps, a search, a chosen result, passenger details and then payment, you can see the step where people stop. A lot of visitors searching but very few reaching the payment page usually points at price or at a slow search, while people reaching payment and then leaving usually points at something in the payment step itself.

Two honest limits are worth knowing. Analytics tells you what happened, not why, so it points you at the problem rather than solving it. Numbers are also approximate, because privacy rules let visitors refuse tracking and their visits will not be counted. Card details and full personal information never appear in these reports, which is correct, but it does mean you cannot follow one named person through the site.

Ask for the tracking to be linked to your own analytics account, so the data belongs to you, then look at your search to booking figures over a full month before drawing any conclusion from them.