To become an IPS, it doesn't matter whether you choose science, commerce, or arts. In IPS exam that mainly conduct by UPSC, it doesn't require any specific academic background; it just needs your graduation in any of these three streams.

If you want to take science after 10th because you enjoy this subject, then go forward. You just need a graduation degree to sit for the IPS exam. So, choose what you want to do and what makes you comfortable. Don't force it on you. To become an IPS, you need good analytical and communication skills with good discipline that helps you in your job.

I hope it helps you.

All the best for your future!!