This is certainly not an entry level task. You can potentially cause some serious damage to your existing database if you do not know what you are doing. However, if you are going to do it anyway, I would suggest looking at Oracle documentation.
It occurs to me that I have seen many questions from folks who seem to have no idea what they are doing. And I do not mean to pick upon this particular individual.)
I have to wonder if some of these questions aren’t from people who got a job and don’t really know what they are doing and the assignments they have been given might be a test from their supervisors.
After all, a “jr level dba” would not be assigned this task without ANY direction, ANY help, and left all alone… unless …
U may use “RMAN duplicate” command to clone / duplicate db. The target / duplicate may be on separate hosts or on the same host.