What was the first langauge spoken in North America?

That's just about impossible to say, since scholars do not agree on migration models and periods, as the site below indicates. What linguistic evidence there is suggests that there might have been several parent languages, brought over from the Eurasian landmass, possibly across the Bering Land Bridge.


https://en.wikipedia.org/wiki/Models_of_migration_to_the_New_World

Here's another site that briefly discusses the language issue:


http://history-world.org/American%20Societies.htm

The first language spoken in North America would have been the indigenous languages belonging to the native people of the land before the European explorers discovered their habitats and settled there.

Native North Americanise

Joseph Greenberg argues that there were three separate population movements from Asia into North America, but this is regarded as rather a low figure by others. Some may have come via the 'land bridge' - itself a controversial entity - and others by small boats. If we don't even know how many different peoples moved over, or what languages they spoke, how can we possibly say which of them arrived first? Even the relationships between the surviving languages are highly controversial in linguistic circles. And apart from this, so many of the languages present in North America have become extinct - not all down to the evil white man - and natural changes will have taken place further confusing the issue. Part of the problem is that until the arrival of the white man there was no system of writing. Users of English, Spanish and French did record some things - in roman lettering - and a Cherokee syllabary (sort of alphabet) was devised in the early 1800s. Apart from that, there are the Central American pictographic systems which give little help to the paleolinguist.