Assalaam Alaikum Wa Rahmatullahi Wa Barakatuh Sis,
I'll try to answer this question in the view of Risale-i Nur.Iman can be described as the belief in Allah SWT in short.
Be certain of this, that the highest aim of creation and its most important result are belief in Allah (iman). The most exalted rank in humanity and its highest degree are the knowledge of Allah contained within belief in Allah. The most radiant happiness and sweetest bounty for jinn and human beings are the love of Allah contained within the knowledge of Allah. And the purest joy for the human spirit and the sheerest delight for man’s heart are the rapture of the spirit contained within the love of Allah. Indeed, all true happiness, pure joy, sweet bounties, and untroubled pleasure lie in knowledge of Allah and love of Allah; they cannot exist without them.
One who knows and loves Allah Almighty is potentially able to receive endless bounties, happiness, lights, and mysteries. While one who does not truly know and love him is afflicted spiritually and materially by endless misery, pain, and fears. Even if such an impotent and miserable person owned the whole world, it would be worth nothing for him, for it would seem to him that he was living a fruitless life among the vagrant human race in a wretched world without owner or protector. Everyone may understand just how wretched and bewildered is man among the vagrant human race in this bewildering fleeting world if he does not know his Owner, if he does not discover his Master. But if he does discover and know Him, he will seek refuge in His mercy and will rely on His power. The desolate world will turn into a place of recreation and pleasure, it will become a place of trade for the hereafter.
Now we should seek the real knowledge of Allah SWT.This is called "tawheed":
The affirmation of Divine unity (tawheed) is of two sorts. For example, if the goods of a rich man arrive in a market or a town, there are two ways in which one may know they are his. One is briefly and simply, as with ordinary people, which is: “No one apart from him is capable of owning this vast amount of goods.” But when under the supervision of a common man such as that, much of it may be stolen. Many others may claim ownership of parts of it. The second sort is this: through reading his writing on every packet, recognizing his signature on every roll, and seeing his seal on every bill, the man declares: “Everything belongs to that person.” Here, everything in effect shows the important man. Similarly, the affirmation of Divine unity is of two sorts:
One is the superficial and common affirmation of Divine unity which says: “Almighty Allah is One, He has no partner or like. This universe is His.”
The Second is the true affirmation of Divine unity which, through seeing on everything the stamp of His power, the seal of His sovereignty, and the inscriptions of His pen, is to open a window directly onto His light from everything and to confirm and believe with almost the certainty of seeing it that everything emerges from the hand of His power and that in no way has He any partner or assistant in His Godhead or in His sovereignty, and thus to attain to a sort of perpetual awareness of the Divine presence.
Therefore the better we know Allah SWT with His actions, His names and His attributes, the more we can strengten our iman.Here are some good sources to get a better knowledge of Allah SWT: