What is your question ? We’ll gladly try to help.

Maybe read this really helpful page first : https://www.seat61.com/how-to-use-a-eurail-pass.htm

Here’s what I want to do but don't know how to schedule or what ticket or days i should purchase. Been awhile since i travel by rail in europe LOL. 1986 was awhile ago and i see that things have changed since then. Im arriving in amsterdam and want to go to narbonne france. spend time there then depart to Lisbon Portugal then after a stay there 2 weeks then train back to Amsterdam. Need advice on how to do. and what amount of time should i give myself for delays etc,etc. 

The Seat61 link that @thibcabe gave is a great start for how Eurail works (it may have changed a little since 1986!). That site also has some suggested itineraries.

For example this page on Amsterdam to Barcelona will give you a good rough idea of the route, to build your own itinerary from.

https://www.seat61.com/international-trains/trains-from-Amsterdam.htm#Amsterdam-Spain

Madrid to Lisbon is a bit of a slow one, but perfectly doable: https://www.seat61.com/trains-and-routes/madrid-to-lisbon-by-train.htm

For timetables, use www.bahn.com. And don’t be afraid to break the journey down into small chunks.

And finally, you need to know that France and Spain (and the Eurostar from Amsterdam to Paris) charge some pretty high reservation fees for rail pass holders. It’s annoying, but that’s how it is. You can sometimes avoid or reduce these fees by taking slower routes.

A good list of what the reservations cost and how to but them, again on Seat61.
https://www.seat61.com/interrail-and-eurail-reservations.htm

It’s a long journey doable in 3-4 days. Unfortunately Portugal is badly connected to Spain : Madrid - Lisbon is a full travel day while we wait for the high-speed line opening in a few years.

I’d do a nice loop like :

• Day 1 : Amsterdam - Paris - Narbonne
• Day 2 : Narbonne - Madrid
• Day 3 : Madrid - Badajoz - Entroncamento - Lisbon

For the return journey something like :

• Day 1 : Lisbon - Porto - Vigo
• Day 2 : Vigo - Vitoria/Gasteiz - San Sebastian
• Day 3 : San Sebastian - Hendaye - Paris - Amsterdam

Unfortunately the direct and so convenient Lisbon - Hendaye night train was cancelled during Covid (a perfect excuse for RENFE :/)...

This is a rough schedule with other options too! For example you may wish to stop in Barcelona or add an extra day in the beautiful Basque country or Bordeaux on the way back, etc.

What would be your travel period ? Summer is obviously a popular time so you’d need to book trains in advance when required. High-speed trains and most Spanish trains have mandatory reservations (extra costs) limiting your flexibility.

Timetables should all be on bahn.com/DB Navigator app as suggested. The cross-border Porto - Vigo train is famously missing as CP (Portuguese railways) and RENFE (Spanish equivalent) do not share everything to the European-wide database. Don’t ask me why!

Have a first look at the link I posted and do not hesitate to come back! :)