Train from Portugal to Spain or France

There are no direct trains from Lisbon to Madrid. The last one was a night train that stopped at the start of the Pandemic and never reinstated. Flying is your best option.

I may be incorrect, but there are no direct trains from Lisbon or Porto to Madrid or Paris.

Portugal just never developed a train system integrated with Spain's train system. At one time, there was a Lisbon-Madrid night train, but everything says service is suspended. But, new services pop up all the time, so maybe something is in the works

You can get close from Porto, by going North to Vigo, but most solutions have you transferring/changing trains multiple times, and taking circuitous routes. To Madrid alone is 8-9 hours, to Paris, 20+ hours.

From Lisbon, there is a central route to Madrid,, but again, most solutions have multiple changes and long waits between trains, adding up to about 10 hours.

If you go South, you can get to Tavira by train, but then Bus to Seville, where you have more high speed train options.

I did do Porto - Madrid a while ago. There are direct trains from Porto to Vigo, and from Vigo to Madrid, so it is only one change. Unfortunately schedules are sparse, and you have to change stations in Vigo.
However the route from Vigo Guixar to Vigo UrgaIz is walkable (and signposted). And I spend the time there having a nice lunch. It is next to impossible to have a bad meal in that part of Europe.

In addition to crossing the Spanish/Portuguese border on a train not really being an option, as mentioned above, Spain's last sleeper train ended service in 2020.