All the big channels today started with 0 subs so it's not true that you need subs to get views. Views drive subs more than the other way around.
SEO
If you're doing SEO to start the ball rolling (and I recommend you do), you have to target longtail, low-competition keywords and phrases that get fewer searches from viewers but also much less competition from other videos. Don't pay too much attention to TubeBuddy's data. The data isn't coming from Google. Use common sense and do a bit of analysis manually. (see example below)
Example of high competition (short) phrase (that you shouldn't try to target): "Minecraft Let's Play" (Done to death. Millions of competing videos)
Example of low competition (long) phrase (that would be easier to rank for): How to chop down a tree in Minecraft" (obviously just an example. I have no if you can chop down a tree in Minecraft )- This is a very specific phrase and that is why it is good. Not many users will be searching for it so it won't get you tons of traffic but that's fine. You need traction. The good thing is that there will be fewer competing videos targeting that phrase so you'd have a fighting chance at getting on page one. With this low-competition phrase, you'd have say a 60% chance of getting say a share of 200 views per day. So decent odds of getting afew views that will add up over time and will eventually result in subs if your content is good. If you'd gone after the high-competition phrase, you'd have a 0% chance of getting a share of 100,000 views per day. So basically you'd get no views from search.
YouTube will "boost" new videos in the search results for about 48 hours to test how they perform. If the click through rate is good and then the subsequent audience retention is good, the videos will start ranking and be promoted. You don't need hundreds of subs for that to happen. But it's essential to only go after the low-competition and long phrases otherwise you'll never rank.
For SEO to work, you need longtail search terms in your title, description and tags. The description is really important. YouTube's algo doesn't watch videos and decide what they're about. You have to tell the algorithm via the description. So many new channels write terrible descriptions that don't achieve anything.
Social media
Build up a following, network, get active, add value, don't spam.