You need to promote it.

Meaning you need to attract people to your channel from other platforms like Instagram, Facebook, other Youtube channels and so on.

if you have specific niche, like filming videos of trains, find forums where people talk about trains.

You need to have some videos already and post consistently so your viewers can turn to subscribers.

And than if you are lucky and your videos fit youtube algorithm it might start promote the videos to similar viewers as yours. Using good keywords is also important for that.

Here are some other suggestions that you can follow to increase your viewers and subscribers.

• Make attractive thumbnail, use HD images with colorful font.
• Tags: Search online for popular tags in YouTube, you can put them in video description (up to 5000 letters). Put relevant tags in video tags section.
• Content: The real king. I don’t know what type of videos you are uploading but make sure to maintain best quality in your videos. Don’t upload all type of videos like entertainment, education, facts in one channel, maintain one type of content. Also you need to grab audience attention throughout the video, please don’t upload boring videos
• Please don’t change your channel name again and again, if you did your existing subscribers won’t get any notifications from your channel.
• Rule: Set one time stamp for uploading videos like for example one video every Sunday 8 AM or Everyday 8PM. Don’t upload videos randomly. YouTube algorithm will work for channels with consistency.
• Patience: Upload videos for six months by following all the above mentioned rules. Please don’t look at YouTube studio statistics and feel sad, YouTube algorithm will start recommending your videos after six months. During initial months your videos will appear to small audiences/channels. So don’t give up.