www.deutschkurse.dw.de helped me out pretty well, I think that has a course that goes up to B2. Other than that, I used duolingo and did an A1.2 course at a german uni which I found pretty easy, but nonetheless helped.

I think we're in the same boat actually; about the same level. Most of my learning is self-directed now. I've read a short German Grammar book front to back (Helped a lot, even if you don't remember anything), and I've got some general easy reading for german, which is very important.

The best thing you can do is just immerse yourself with trying to read, write, speak, listen as much as possible; this gives you confidence and teaches you lots. But in all honesty the best way to learn "properly" is in a good german course, like B2 for you etc. However of all the things I will recommend most: Three steps to fast improvement:

1: Download a GOOD german dictionary app. On android I use "Ger-Eng Dictionary" which searches as you type. (I paid for this app but it has paid back in spades)

2: Actually use it as frequently as possible. Thinking of a word, in english that you don't know the translation to? Search it. Read or hear a german word you don't know?? Search it. Want to find similarly meaning german words (IMPORTANT)??Search it. Don't know a noun's gender?? Search it

3: Use an actual german resource, like a 100% german dictionary, and actually use it. It's how we learnt english.

I am constantly checking my dictionary app. Some days, 30-40 times I will search for words because I'm living here and talking to people. It's also nice and discrete, and I can do it mid conversation, and then use/understand the word in context which means it's more likely to be remembered.