How to learn fast in a new language ?
First thing is you should have honest willing to learn it quickly. Time you have taken to learn anything depend on your effort and interest. As well as you should find out a good teacher as well. Or else if you can find out your colleague who know that language well also a good option as you can see the way he/she is talking and you can practice some speaking sessions with them. Reading and listening also a good mechanisms to learn new language quickly.
It all depends on your teacher and how he teaches you I guess. Of course, the most important thing is to work hard but the teachers matters too. I recommend you to try some of the teaching platforms like that one from https://www.robotel.com/smartclassplus/modern-language-labs-defined/ I mean, look for a teacher who uses such modern things and can help you with learning. I think it will be the best way to learn for you, good luck with it 😉