Learn Spanish (Latin America): Tenemos que mejorar la tecnología, o la nave no funcionará. - We have to improve the technology, or the ship will not work.

To form the future simple of a regular verb, you do not drop the -ar, -er, or -ir ending. Instead, you add the future ending directly to the full infinitive. Here, we take funcionar (to work) and add -á because the subject is la nave (it), giving us funcionará (it will work).

Could I say la nave no trabajará since trabajar also means "to work"?

No. Trabajar is only used for people or animals doing physical or mental labor. When talking about machines, systems, or devices working properly, you always use funcionar.

Why is the word que included in Tenemos que mejorar?

The phrase tener que is a set expression that means "to have to" do something. It is always followed by an unconjugated verb (an infinitive), like mejorar here. If you left out que, it would just mean "we have," as in physically possessing something.

Does la nave mean a boat on the ocean?

It can refer to a water vessel, but a standard boat or ship on the ocean is usually called el barco. La nave is very often used to talk about a spaceship (nave espacial) or an aircraft.