How is it possible to reconcile long working hours in the restaurant (from 11:30 AM until 10:00 or 10:30 PM) and dealing with food and its smell while fasting, knowing that Iftar time in Belgium is late (7:12 PM), and is it permissible to break the fast at 3:00 PM and make up for the remaining hours? What about the situation in the future when Ramadan approaches summer and fasting hours become much longer (Iftar at 10:00 PM and Fajr at 1:00 AM)?

It is not permissible to offer food to those who are not fasting during the daytime in Ramadan (definition), whether they are Muslims or disbelievers. This is because disbelievers are addressed by the branches of Islamic law, and doing so constitutes assistance in sin. One must search for another job. The fast of a day must be complete; fasting only part of it is not sufficient. Allah Almighty says: "And eat and drink until the white thread of dawn becomes distinct to you from the black thread [of night]. Then complete the fast until the night." Fasting is obligatory during the long summer days as long as there is day and night, unless the fasting person fears for their life or falling ill, in which case they may break their fast and make up for it on other days.