Day Questions

Sometimes when I feel sexual attraction, there is an involuntary discharge of liquid, which may or may not be followed by semen. Will I need to do the ghusl of janaba?

If the semen was released, then ghusl must be performed before offering the prayers. The release of another fluid, such as what may be released during foreplay and sexual urges does not obligate ghusl.

If an unbeliever asks me to help him pray to Allah so that his legitimate desires be granted by Allah, can I do so? And if he gives me a gift for it, can I accept it?

You can pray for their guidance, and you can also accept their gifts. Religious narrations encourage good behavior with the unbelievers.

Is payment of Zakat on any amount of money obligatory and what are the conditions to be met, if any?

It is not obligatory to pay the Zakat on cash, as it is not one of the nine things upon which Zakat is obligatory. However, it is obligatory to pay Khums if the necessary conditions are met.