I'll tell you how to grow youtube channel from such a low level to make it become one of the most popular YouTube channels.
Choose the right content
If you'll ever succeed on YouTube you'll have to sit down and consider what you love talking about and what you love to discuss with your friends. Once you figure out that, that content is the same content you have to start a YouTube channel on. Now why is this important? well people can smell your enthusiasm or lack of it right from your videos and if you don't seem to be passionate about the subject you're talking about no one is ever going to subscribe to your channel. If you choose topic just because you want to make money you'll fail while making money on YouTube is fun if the subject you want to make videos about isn't the one you talk about with your friends all day you won't enjoy making those videos and if you don't enjoy making the videos people won't enjoy watching them.
Think of it as a business
Start a YouTube channel with the mindset of starting a business means you understand that you are in a serious task. Plus, no business is easy, so many people expect you to be easy because they think it was used as a hobby well that was in 2007 with more than 3M people having a YouTube channel seeing it as a hobby is like seeing competition with million dollar company as a hobby. So many people want a quick result again this is because most people never really build anything in real life. I know what it takes to build things it's a long walk to freedom and if you want success in 6 months then you don't need success. I met a man who told me that he posted about 3 videos on YouTube and since nobody watched them he stopped posting, don't do that, people publish more than 450 videos before they started making money here on YouTube. It's a serious business if you don't want to wait, don't start.
Don't beg for subscribers
Don't waste your time begging for subscribers. Another thing I think most people don't get here on you tube is that subscribers to your channel don't mean anything much. A lot of new channels are busy begging other channels or people for subscribers. It's a waste of time instead focus on creating the kind of content people want to watch and they will subscribe anyway. Promoted your channel on our social media but the best thing is focusing on creating content that attract views.
Thumbnail
The main thing that is going to help grow your channel is to have a good thumbnail. You can make thumbnails on Canva, you can make them on get stencil or you can pay somebody to make them. If you can't have something to catch people's eye they're not going to click it.