i am not able to boot my macbook pro 2009 model

MacBook Pro 2009, or iMac? I don't understand. We need to know the exact model of the Mac you want assistance with here. If you have access to other Macs, then that is fine, but please make a clear distinction between them (also helps to know their exact model as well). You can get the exact model by clicking the Apple menu and selecting "About This Mac", or if the Mac is not booting then enter the system serial(s) here:

Check Your Service and Support Coverage - Apple Support

The only way to make a bootable macOS USB installer is by using a Qualifying Mac and the instructions in this Apple article making sure to use an OS installer that is compatible with the Mac you want to boot/reinstall.

How to create a bootable installer for macOS - Apple Support

If you have a Late-2009 Mac which had macOS 10.12.6+ installed at some point in the past, then that Mac should have access to Internet Recovery Mode (Command + Option + R) to access the online macOS installer.

If your Mac originally shipped with OSX recovery 10.6 DVDs, then you will need to use them or possibly a retail version of the OSX 10.6 Snow Leopard upgrade DVD --- which one depends on the exact model of your Mac you are trying to restore/fix.

nikunj23 wrote:

Hi, so I am trying to reset an old IMac I have been given and there are 3 main issues.

1) no start up disk showing

2) the USB drive I downloaded doesn't show up when I start in recovery mode. It is plugged into a USB drive and in disk utility it does show up but doesn't show up at the beginning for me to click install.

3) aslo not able to recover my os by store

How can i fix these 3 main issues please?

If your Mac doesn't turn on

If your Mac doesn't turn on - Apple Support