What are the prescribed objects for the development of jhāna? Can i have a list "If there is one" of the different objects for building up the first jhana?
Saṅkhitta Dhamma Sutta mentions the Jhana can be developed through:


4 Satipatthana
4 Brahmavihara


Kaya,gatā,sati Sutta mentioned that Jhana contemplation of the body. Though not explicitly mentioned Anapanasati Sutta, breath meditation also can be used.

Do develop Jhana you have to have Vitakka &amp; Vicara. That is you 1st bring your attention an object and retain the object by reapplying you attention. E.g in the case of breath meditation you continuously try to feel the breath going in and out. In case of body contemplation you try to feel any sensation in the body continuously and try to keep you attention on the body.

This is too short to be practical meditation instruction just a pointer. In the case of Kasina you look at the device. Say you are practicing on fire. Offer a lamp to the Buddha, Dhamma and Sangha. Look at the flame for a little while and shut you eyes. Try to recreate this image. When you think about it the image will pop up an linger for a while. When the image disappears rethink about it again. If you cannot remember the details look at the flame again. As you practice the image will linger for a little longer. Adjust the rhythm of thinking about the frame to roughly to the level that you mental image of the flame looks continuous. Similarly for any other Kasina device. Beyond this point best seek advice of a teacher.

I think Jhana developed through 4 Satipatthana in combination with 4 Brahmavihara would be the best approach. But having said this any of the 40 Kammatthana can be used. If you use anything other than 4 Satipatthana make use you contemplate the 3 characteristics of the Jhana otherwise you will just develop Samadhi but not Panna, hence will not be wholesome.

Finally, developing Jhana without proper guidance can be dangerous. Therefore, try finding a teacher who can guide you.

Currently one of the famous Jhana teachers is Pa Auk Sayadaw with many students in the west. You can try making some inquiries.