Hello, little_kosh!
Your current level is stated as Upper-Intermediate (B2). Your goal is reaching C1/C2 level in a year in order to use it fluently in the professional field. It takes in average 200 hours to get to the next level. You should keep it mind while planning.
Also, you stated about the need of professional vocabulary. Which one voc is this? I`d like to find some for you. Anyway, I hope these recommendations will help you. May the determination be with you🙂
First of all, analyze what prevents you from fluent speaking.
Fear of Mistake
In terms of possible solution to overcome is to understand that mistakes are normal. Nobody is entitled to shame for them. Even a teacher. Try to test a teacher or a correspondent speaker for welcoming mistakes, before you start to believe them. And the mistakes will not bother you so much. For example, try to speak publicly gradually. I mean start with your friends and speaking clubs with warm atmosphere to encourage yourself. Only than go to public like audience, work, negotiations etc. The same approach is for fighting shyness (devoted for introverts).
Anxiety
Anxiety is a feeling of tension, apprehension and nervousness associated with the situation of learning a foreign language. Among other affective variables, anxiety stands out as one of the main blocking factors for effective language learning. It can influence the quality of oral language production and make individuals appear less fluent than they really are. To overcome anxiety is to practice more. More talking, more writing, more reading etc.
Lack of Confidence
It is commonly understood that students’ lack of confidence usually occurs when students realize that their conversation partners have not understood them or when they do not understand other speakers. In this situation, they would rather keep silent while others do talking. In response to this, maximizing the exposure to English is a good way to build the confidence. In line with this, regularity matters. Along with practicing proper pronunciation and intonation, and to converse freely. By doing this, students will experience a greater sense of ability to speak English.
Lack of Motivation = procrastination
It is mentioned in the literature that motivation is a key to students’ learning success. In this sense, motivation is a key consideration in determining the preparedness of learners to communicate. It has been proven in many studies that students with a strong motivation to succeed can persist in learning and gain better expertise than those who have weaker motivation of success. To fight that you should rest more and make smaller steps instead waiting for a massive result instantly.
Let`s start with vocabulary as you stated this as your priority.
Step 1. Build your vocabulary as a system
Language words form a structure with its own peculiarities. If you know the origin of the morphology of the word it is more likely that you`ll guess the meaning without translating. To know more how to do it: