My laptop sudden started showing the detail boot manager file missing. Then I installed a new copy of Windows 7 32 bit., And after installation no drivers like wifi, or usb has been found. Laptop is not detecting any pen drive or wifi connection. Facing big trouble in using laptop.
You need to re-install the drivers for your specific laptop model from that laptop manufacturer's website.
"I installed a new copy of Windows 7 32 bit"
I'm guessing you used a retail Win7 disk rather than the recovery partition, because the recovery would have all the drivers. You might be able to find the drivers at the laptop manufacturer's website IF Win7 is a supported OS. If it's not, you will have to identify the make/model of the hardware (chipset, graphics, network, audio, etc) & then search for the individual drivers. Had you posted the make/model/model number of your laptop, one of us would have been able to help.
If you haven't deleted the partitions of the old windows installation, the recovery partition should still be there and you can assign a drive letter to it in the drive manager.
After that, you will find all the drivers on that drive for installation.
I recommend ONLY getting drivers from system manufacture's site for complete systems and component manufactures sites for built computers and changed out hardware. For graphics cards the site to go to is your GPU manufactures site (NVidia or AMD). These are the only completely safe and guaranteed up to date drivers as long as you select the correct models and versions.