How would the structure of a course be for me?

My idea is to hire a year 4 times a week in their course

I started learning English at 38 years old due to the need for work, I only learned it by listening and then with technical manuals

I have been in contact with the language because I work with a company from Austria and another from Sweden

Well, I don't have an English structure, I want to learn it well to be able to apply for important positions

The point is that if I start with something very basic I get bored. Now I have some time and in turn I am 61 years old

Could you tell me how would be the articulation of a course for me?

Thank in advance