What is the ruling on breaking the fast inside the mosque when there is sufficient time to prepare food and a good salary, and are there any conditions for that?

There are no conditions for breaking the fast in mosques, unless those who provide the iftar meals or the funds spent on them specify certain conditions for benefiting from them (e.g., that they are for the poor, or the worshippers, or the mosque community, or the homeless). In that case, it is not permissible for anyone who does not meet these conditions to break their fast with these meals. This is because Islamic law obliges adherence to the condition of the donor or endower, as long as it does not contradict Islamic law.

However, if the donors do not stipulate anything and make them available to all fasters, then there is no objection to any faster breaking their fast with these meals, even if they are well-off, with a preference for those who are not in need not to inconvenience those who are.