PGDM (Post Graduate Diploma in Management) is a diploma degree issued by AICTE (All India Council for Technical Education) recognized institutions in a 2-years full-time program. B-schools offering PGDM course are autonomous bodies with an industry-oriented curriculum which allows them maximum flexibility to constantly keep updating their course curriculum adapting to the industry development. It is at the par with the quality of education imparted to students pursuing an MBA degree.

PGPM (Post Graduate Programme in Management) is not a degree but a certification course. It is a typical 1-2 year’s program and doesn't possess any sort of recommendation as it is generally offered by colleges without affiliations.

The biggest difference is that PGDM enables you to pursue higher education like PhD but a PGPM program doesn't facilitate you the same.

Being a fresher candidate it doesn't matter whether you do PGDM/PGPM/PGP/MBA. This question arises for the candidates who have more than 5-year work experience so whether they should do a full-time MBA or executive MBA. But in your case, there is no dilemma you should mainly focus on getting a top b-school rather than worrying about the degree. Better the college better will be the value of your degree irrespective of which degree it is and you don't need to worry about being a fresher as in top institutes like IIMs also 20-30% of students are freshers.

All the best!!