It is necessary more than a goal-set to achieve a good level of English, actually, if you really want to get the fluency you want, be prepared to accept that nobody has an UTTER English, not even native speakers. If an utter English is almost an impossible mission, get an UTTERANCE communication is achievable.
Speaking a language well is the ability to communicate properly your ideas, we called it in English: utterance message, which is nothing more, nothing less, than an intelligible speech. Not all native speakers can do it.
Do not go that farther, there are a lot of Brazilians, perhaps, one next to you, who can't express their ideas in an intelligent way. It doesn't matter if you have a fantastic passive knowledge; if you don't know how to articulate it well, people will never understand you.
During your journey to became a speaker, many will be the difficulties to master the language, and it has nothing to do with grammar and vocabulary. You will have to turn your student mind into a learner one and to do so, you will need to have GRIT and pass through all theses phases in order to cross to the other side:
Laziness phase: you will face a laziness period, when you won't feel the " will" to study by yourself, you won't even feel like going to the classes - Have the grit to keep moving is something that all leaners have to develop by themselves. No teacher can help you with that.
Fear phase: you will be afraid to speak with a native or any other person who ( you think) speaks better than you - knowing how to tune ( level up or down) will be the only way to face it.
Disappointment phase: you will be very disappointed with your progress, due to one or another experience where you couldn't remember a words or two - or perhaps due to a minor error that have made you think that you don't speak English at all - knowing that nobody has an utter English can help you to not push yourself too hard.
One can't be that naive to believe that learning a second language is something that you will achieve in a few weeks - effort, patience and grit are the best tools that you can use to face all those difficulties and many others more during your journey to become a good speaker.
Although there are so many barriers separating you from your utterance message; I can guarantee that if you could read until this point and understand the aim of this text, you are already half way there, therefore, don't surrender, don't give up and keep up.