The most legitimate way to gain followers and to grow followers is that you end up firstly and most importantly find the niche, finding something that the targeting audience is actually looking for in terms of content. At the same time, it is important to at least be posting regularly. Figure out the Instagram algorithm to understand what really is gaining attraction like recently reels are the ones that have become more popular.

So actually keeping track of what people are doing and the market is gaining popularity. What kind of content your audience wants to see that is something which is very very important also somewhere I believe that following the correct set of people and in a way having the correct set of replies or comments on a lot of other people's posts which is intellectual content, not random-contact that helps you to gain a lot of attraction because people then start listening to you and the consider you as a person who is a subject experts, you know what to speak.

These are few points that can really be done to grow your legitimate followers on Instagram