1. The certificate is useful, you can present it to any organization and leave the decision on them wether to tesr the skills claimed, to have acquired or not 2. You will not learn a language untill you code with your own hands. Like most skills, you need constant practise. Watching YouTube lessons is fine but it goes back to writing the code by yourself. additionally, I prefer textbooks due to the detail context they provide... Personally, I think learning with YouTube will have negative impact. Another best way to learn is by reading other's code, run it and figure out how they works 3. Glad you're in the middle of python course, sololearn teaches the "basic".. or if there's something lower than that. I'll suggest you get the book "a practical introduction to python" to learn further 4. It's just 2 questions which I personally think it's not too much... However, I don't think it deserves an upvote cos it's just regular question people ask
If youve learned about python to where you think you know enough, go practice making simple and easy projects to really test what you have learned. When you get stuck ask a question here or your answers may be in the courses.