Tbh man you're better off studying and honing in on what exactly niche it is you're targeting and focusing on building within that niche.
Gary vee did a few vids on this some years back I think $1.80 instagram strategy but it would go something like this.
Lets say u make music similar to an artist such as Justin Bieber.
U would find several similar musicians(harry styles, zayn, shawn mendes, charlie puth, etc.) follow them on Insta and then turn on their post notifications. From the moment they make a post, u would then begin to slowly engage w the ppl who are instantly engaging with that post.
Within those accounts that are actively engaging w posts, u want to find the ones that are public accounts and immediately view their story, like a couple posts and then leaving a genuine comment of some sort. I'd say make note of these accounts ur engaging with so you can keep it up over time to build a long lasting relationship.
Ideally, u'd want to do somewhere around 20-30 accts per day while following this method and over time this will help you build up somewhat of a community on your account then you can direct that traffic elsewhere.
I'd say this in addition to running ads AND paying for promos/shoutouts also within your niche would bring outstanding results if you're 100% certain on what your target audience is