If your family are in Jeddah and you are living in Makkah only for the purpose of study and you do not have a family there, then if you are in Jeddah and want to go to Makkah for Hajj, not for study, you have to enter ihraam from Jeddah. The same applies to your friend, if he lives there but does not have a family there and he forms the intention to do Hajj when he is in Madeenah, he has to enter ihram from Dhu’l-Hulayfah. The fact that you want to work during the Hajj does not permit you not to enter ihraam from where you are, because you have decided to do Hajj during this journey and the Prophet (blessings and peace of Allah be upon him) said, after describing the miqaats: “And these meeqaats are for the people at those very places, and besides them for those who come through those places with the intention of performing Hajj and ‘Umrah.” Narrated by al-Bukhaari (1524) and Muslim (1181).
Shaykh Muhammad al-Mukhtaar al-Shanqeeti (may Allah preserve him) was asked: if a person is studying in Makkah throughout the year but is not one of the local people, and he went to his home city then came back to perform Hajj, when he comes to the miqaat does he have to enter ihraam from that point or is he regarded as one of the people of Makkah and is it sufficient for him to enter ihram from there?
This matter is subject to further discussion. If he is going out to his own city or to visit his family before the months of Hajj begin, then he enters Makkah before the months of Hajj begin, in that case he should enter ihram for Hajj from Makkah, and he comes under the same rulings as the people of Makkah, because the time of Hajj has not yet begun.
But if he left Makkah after the month of Shawwaal began, then he entered Makkah from any direction, then he comes under the same rulings as the people who entered the city from that direction and he should only enter with the intention of doing ‘umrah, or enter without any such intention, then when the time for Hajj comes, he should go out to the miqaat that he passed. The reason for this is because it is the time of Hajj, and if a person passes by the miqaat at the time of Hajj and with the intention of performing Hajj, then he has to enter ihram from that point, and this is in compliance with the hadeeth “And these miqaats are for the people at those very places, and besides them for those who come through those places with the intention of performing Hajj and 'Umrah”. So he passed the miqaat, intending to do Hajj after the time for it began, so he has to enter ihram from this miqaat. In that case it should be said to him: Either enter ihram for ‘umrah then exit ihram until the time for Hajj comes and you enter ihram for Hajj in Makkah; in that case you are doing tamattu‘ Hajj and you have to offer a sacrifice; or you may pass the miqaat without entering ihram, then when the time for Hajj comes, go out to this miqaat and enter ihram from there. And Allah knows best.
End quote from As’ilat Sharh Zaad al-Mustaqni‘
And Allah knows best.