What is the Power Supply?
The Power supply(PSU) is mainly what powers the whole computer. This component is determined by watts. So it depends on how much the total amount of watts the computer consumes. for example there are PSU as low as 450W up to 1200W. Try to find a sweet spot on which you need. too little will not power the computer at all, and too much is just a waste especially money wise. let me give an example, if you are building a basic computer with basic components and not use very heavily, then you might want to go with a 450W PSU. but if you are planning to add a gpu in the future, then you might want to go with a higher wattage, like 650W. there are also ratings like bronze, silver and gold certified which means power efficiency. for example if there is a 100W power supply and has an 80 plus certification then it has an 80% effeciency meaning it will draw 80W.
Corsair CX 450W
i have choosen this power supply for this build because this is an 80+ bronze certified PSU and it is enough for the computer that we will be building. it is a non-modular power supply meaning that all the cables will be connected on the PSU so there might be some cable management to be done to make the inside look neat and clean.