Is it possible to get rid of misgivings related to Allah's power, such as His power to make the world undeveloped, and how can one feel Allah's power without these misgivings?

Your questions confirm that you are afflicted with waswas (obsessive whispering). You must turn away from thinking about such matters. Occupy yourself with memorizing the Quran, reading books on spiritual edification (raqāʾiq), and stories of the Salaf. Beware of sitting alone, and associate with righteous sisters who are obedient to Allah. Reflect on the stories of the prophets and observe the cosmic signs to discover the proofs of Allah's power.