Well, there are so many free applications and web tools available on the web and application stores through which you can easily hike up the number of followers and likes on your posts. the application like Hublagram, Social Rocket for Instagram, IG Autolike are some of the most common ones which variant number of users use to increase the number of followers.
There is no limit of increasing the number of followers you are free to increase the number of followers and likes on a particular post. But every time you boost up the followers or likes you have to wait for 15 minutes if you want to boost again.
'Hope it was informative'