While you filled up the HR forms you could have provided previous PF number and HR could have arranged to submit for PF transfer thru your previous employer.
You may visit local O/o PF commissioner in your city and obtain forms for withdrawal/transfer, and understand the process from PRO.
EPFO directory can be accessed at:
https://www.epfindia.gov.in/epfo_directory.htm
If you keep the a/c regular for 10 years you shall be eligible for pension.
You may submit the PF forms to previous employer by redg. post under acknowledgment and follow up by email and try and obtain confirmation even if by email that PF forms have been received by company. Company shall attest the forms and submit to o/o PF commissioner and is duty bound to supply you the acknowledgment issued by PF office. You may request to supply the acknowledgment to you by redg. post.