Just bought new parts for my computer, cannot boot my window 7 32 bit

Hi, I just bought a new, CPU, Motherboard, PSU, and casing, and I take my graphic card, ram and HDD/SDD from my old computer. I put them on to my new computer, then turned it on, but then it says windows cannot boot, I pick the right HDD for my windows folder, and it says to repair, and I tried the repair mode, but then it says windows cannot repair this, and i only can click finish and shut down my computer.

I told the people who make my computer (the new cpu motherboard, psu and casing,) that i have window 7 home premium 32 bit. I do not have the CD for window 7, but if nothing else that i can do,

can I buy the window 7 home premium 64 bit, and install it in my new computer? and also my casing does not have cd drive, can i use external cd drive to put the window 7 cd? or it wont recognize it?

obviously its better if i can fix my computer without buying the window 7 home premium 64 bit, i can't give any information about the types of ram and graphic card, because i'm using my friends computer, and i forgot to bring the list, but hopefully next week i can bring the list, but i'm pretty sure that all the components is compatible.

CPU- Intel Core i7-3820 3.6Ghz LGA 2011 CPU No Heatsink
Motherboard- Asus P9X79 LGA 2011pin 8 X DDR3, 3 X PCI-E Motherboard
Graphic Card - I know its NVDIA old type, but i can't remember the name, but i dont think it matter with the booting up for windows?
RAM - I don't know which type, but its 8 gb and i know 32 bit cannot go above 4 gb
Power Supply - does not concern? but might as well, its 1050W but i dont know the type, i got it from my friends and its made in china o.o

I wouldn't necessarily expect the new PC to boot if you simply transferred the hard drive from an old installation, rather than doing a clean install.

Do you have a valid 25 character Product Key? If so, you can download a legal Windows 7 ISO and install from it.

You should not have to buy another version of Windows.

If you want 64-bit, you would have to do a clean install, regardless.

I am reasonably sure that you can download a 64-bit ISO and install from it using the original Product Key, even though you originally had 32-bit, but someone else should confirm that.

Your PSU may be good or bad, but you don't need even half of 1050 watts.

I assume you do not really mean your CPU is not using a heatsink?????