PSP 3000 4.21 CSO or ISO

I git a PSP3000 system software version 4.21

1. What do I need to run CSO or ISO? any additional software/ firmware upgreade for PSP needed?

2. Where to put CSO or ISO on memory stick? Is copying direct to memory stick with card reader from PC ok?

3. Do I need to have UMD in drive to run CSO or ISO from memory stick?

4. What is the highest GB for memory stick and PSP 3000?

PSP 3000s arent able to run custom firmwares at the moment

1 answer for all your questions

a psp 3000 cant run ISO/CSO for now, because a custom firmware is not able to be installed