The easiest way to do this is to buy Instagram followers
Also, you can use Hashtags. This may sound basic.. because it is basic, but using proper hashtags to your photos can increase your engagement by a lot!
Use good and vibrant avatar colors, the good use of colors is important, if your avatar is low quality and dark, you won't be as followed as you would with one with vibrant and good colors. Black can give the impression of mysterious but it needs to be used right!
Provide good content, if you post good photos with proper hashtags you will be seen for a lot more people than you would be with some random photo of a spoon.
You can also research your hashtags, with some tools you can get data about hashtags, what will make you more seen, #food #ilovefood, you need to do proper research.
It isn't impossible to gain 100k followers. A year might be to little but hey if you can put your mind to it I don't think it is impossible. You are going to have to put a lot of work. I have thousands of followers since starting Instagram a couple of months ago.