Praise be to Allah, the Lord of the Worlds; and may His blessings and peace be upon our Prophet Muhammad and upon all his Family and Companions.
Taking interest-based loans is forbidden. It is among the major sins and a known fact in Islamic Sharia. See the Fatwa: 81364 and 81524.
We can deal with this wide spread problem by enjoining good, forbidding evil, exhorting people and reminding them of the bad consequences in this life and the next life.
If your manager orders you to deal with the interest-based loans do not follow him. The Prophet (Sallallahu Alaihi wa Sallam) said: "There is no obedience for any creature in disobeying the Creator" . Allah Says (interpretation of meaning): {… And whosoever fears Allâh and keeps his duty to Him, He will make a way for him to get out (from every difficulty). And He will provide him from (sources) he never could imagine. …} [65: 2-3].
If your work in this company is related to interest, even with writing or giving, leave alone direct involvement in taking loans, then it is forbidden and you should give up working in this company.
Allah knows best.