Greenlanders could vote to be completely independent, yes. That is the situation right now.
However, Trump has done everything to turn Greenlanders away, and not done anything to convince them of independence would be good for them, so a vote for independence will likely fail catastrophically right now. Independence is many decades away, as they would really have to build a stronger economy to make it happen, but that is the direction Greenlanders would like to go, at least if you asked them 2 years ago.
The "independence" of Greenland under Trump would be identical to the "independence" of Venezuela following the US' abduction of its leader & murder of 100 people during the operation. Whatever Greenland's opinion on independence is, what's on offer by Trump would only be worse in every way than what they currently have.
Not in a meaningful way which Greenlanders would submit to. There would be constant unrest and civil disobedience, nothing would function, and bringing in your own people (including the armed forces) to keep things barely working wouldn't be a solution either.
Unfortunately Greenland as a whole has 50.000 people in total of which 20.000 live in largest city and the rest scattered across 19 others.
Thats about the size of a small town in the US, the country may be big in territory but not in population.
It happens all the time. America and the EU are bought and paid for. The funniest part is that they’re being paid for with the very money the buyers plunder with the left hand, only to use the right hand to purchase the treasonous dominant class.
It’s like a sleight of hand magic trick pulled on an infant that is then gleeful for the deception.