Files and Folders Permission

Hi,

Good Day Everyone.

Everytime I copied files and folders from other mac computer or LAN I can't open it.. Maybe It's in read only.. What will I do to make all files and folders to be in read & write state. I want all my mac computers will be in read & write state at all time or everytime I'm copying or transferring files.

I want all files and folders copied from other mac computers, networks, etc. to my mac computer must be in read write state automatically without changing the permissions (using command I). Is that possible?

Please help me..

Thanks

Use the same account name and password on all macs.