Trending @Capgemini; Internal moment
How often I could get selected for the IJP. What is the chance if getting selected if have eligibility for IJP

If you meet the criteria, which means you have completed 18 months in the project to be eligible for the IJP, and then, secondly, you have the right skill set for the said opportunity - apply for it, and if you’re selected, you will be tagged/transferred.
There are no other challenges.
I’ve seen that happening, and if you’re thinking that your current project might not release you, then don’t sweat in it.
I have seen scenarios where the resource was a key resource in the current project However, was eligible to apply for IJP, was selected and hence it was purely on the resources discretion whether to stay back or to move.
Be rest assured that your existing project manager or engagement manager has no control in that, unless you are in PIP

First you should have completed min of 18months in you current practice. Next is you would get the IJP emails atleast 1ce a week. Reach out to the respective recruiters spoc mentioned in the email and check the JD. But dont just goof up things, since its internal your RMG would have your history so is your N+1.