Can anyone give me some help with directions driving from Zagreb to Plitvice Natl Park? My GPS finds Entrance #2 but I need Entrance #1 to join one of the boat tours. Again the GPS says 1.5 hours; does that sound correct? Any help will be appreciated.

I hope this site is helpful: https://np-plitvicka-jezera.hr/en/pl...w-to-get-here/

Boat tours? There is a boat, but it is in the park, unless you are looking at some other place. It is not a tour, just a boat that traverses part of the park (included in the ticket.)

just get to the park, it’s all very well marked and there is nothing else around.. just go to whatever entrance you want when you get there.

Right -- there's no boat "tour", just a ride or ferry on the lake. It's optional. There's a bus service between entrances and you can use this to get back to your car if you plan to walk through the park one-way. We were advised by a local to leave our car at entrance #2 and bus back from entrance #1. We did that and it worked fine but it wasn't necessary. This place is beautiful and you'll love it. It's also popular and crowded. Arrive early if you can and allow time to wait for the bus. If you're day tripping from Zagreb it will be a long day. 1.5 hours each way sounds right.

There <are also buses between Zagreb and Plitvice

The entrances are a short drive from one another; here's another site which has a map that might be clearer to understand.
https://triptins.com/plitvice-lakes-national-park-map/

And to state what others are saying, there are no boat "tours", but several ferries that traverse the lakes.

DOnt I need to buy a ticket for "Tour Program A, or Tour Program B, etc.? Or once you get in the park do you just guide your own tour?

There is one ticket. Once you have that, you can do whatever you want inside. If you want a guide though, I believe you can get one by emailing the park office.

Hold on to your ticket - you need it to board the boats.