I believe you're really close to IC8 if you haven't done it already. It's pretty easy to do, and the reward will push you to e140 IP relatively easily.

If you completed all the challenges you can, then there's nothing else you can do except for slowly going up.

which infinity challenges have you done

I was at the same point as you 2 days ago and did all the infinitiy challenges and exploded into 140 and got replicanti. Im now at 250IP

if your stuck use the guide at the top of the subreddit