The earlier PSP 2k models are permanently hackable, meaning you can use a Pandora's Battery and a magic memory stick to install a permanent custom firmware. Later PSP 2k models as well as all 3k models are not permanently hackable, you can only install lite cfw.
Then go into the recovery menue and deactivate all plugins. If that doesn't work you can try reinstalling custom firmware by using the recovery menue.
But now i have installed a cfw and i tried deactivating all plugins but that didn't work and i cannot install a cfw from the recovery menu
I am sorry to tell you, but if you did not have a CFW installed before and cannot use a Pandora's Battery (which only works on permanently hackable PSPs) your PSP is beyond repair. You can use it for parts, for example get a working PSP 2k with a broken display on ebay or craigslist and switch the screens.
can i ask a stupid question did you remove the battery to maybe see if the battery was bad also remove your memory card and see if it starts up if it fails to boot without the battery place the battery back in and try again with the memory stick removed