What is the ruling on entering into a state of ihram from home or from the miqat for a person who came to Makkah with the intention of working and wants to perform Hajj?

Since you came to Mecca with the intention of working and then intended to perform Hajj, your assumption of ihram for Hajj should be from your home, based on the Prophet's (peace and blessings be upon him) saying: "And whoever is short of that, then his place of ihram is from where he started, even the people of Mecca assume ihram from Mecca."