How to increase skill level?

Question

C++ / C#

Hello. Straight to the point.
I worked in the same agency for six months, there was no advancement in the skill at all. After six months I was looking for a job and found, it seems, in the norms of salary, but again, no growth as a specialist. I am the only web developer in the company. While I was looking for a job, I was an intern at one company, I got a lot of experience, in just a month, and most importantly, I wanted to go to work there (I was there even on weekends, because it was interesting), but they didn’t take it, because I still didn’t reach their level. Now all interest has dropped to zero. I just don’t want to work, because there is no growth, I pick 1-2 sites and that’s it. I can smell how I'm starting to degrade in terms of development.
The essence of the question: how to start raising the level of the skill, because there is no mentor, as in an internship, who will direct you where you need to and tell you. And I don’t want to hang around at all, I want development, but reality is suffocating.
UPD: I’m even ready to work remotely, like on an internship for a company, where I will get skills, teamwork, etc., but, alas, there are none

Answer 1

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Answer 2

By analogy:
If you need to pump up the press - will you also look for a mentor who will cheer you up? Do it yourself, albeit not right, albeit crooked - but the experience will accumulate.

• Find a couple of small tasks on freelance sites - do them "just like that". no need to wait until the customer approves you and the amount suits him - just make a decision for yourself to raise the skill. This approach will save you from one of the problems - "what to train on."
  Yes, many will say that this is a waste of time. Yes, but you will gain experience, which is exactly what you need.
  PS. I myself, with a lot of free time - I begin to engage in such "social ononism" - I help friends and small customers.

Answer 3

Have you tried reading books?

Answer 4

The essence of the question: how to start raising the level of the skill, because there is no mentor, as in an internship, who will direct you where you need to and tell you.

The answer is simple: by your own efforts.
This is how 90% of programmers get up. Situations when there is an intelligent mentor who will always prompt and indicate the direction in which to move (and explain why it is necessary to do this and not otherwise) are exceptional cases from the category of "very lucky".
I was promised at my current job that there would be a mentor and a code review. In fact, there is neither one nor the other.
This is such a harsh life.
I'll tell you a secret - if the skill is low, then your code will still need to be rewritten. It’s still not known what is easier - to write it yourself from scratch, or give you a task, then delve into what you are coding there (and this is the norm for a junior), then point out mistakes, and in the end you still need to almost behind your back stand and say what to write (if the level is really low).