No, it is not impossible at all.
In 2 years of dedicated effort you can learn the basics if you don't try to speak like Cervantes or Shakespeare.
That is, people, after 20 years may have a blunder here and there, but can COMMUNICATE.
That does not mean they are "perfect." "Nobody's perfect."
The main point is to have a "purpose" to learn it and use it. The more you learn and use it, the more you will enjoy it. And native speakers will help you to correct mistakes.
Is it impossible to climb to the top of a mountain?
If you don't walk, hike or climb, for sure it will be impossible. If you practice, get enough training, get enough food and water to keep going on the road, you will get there!
Seriously.