Create and read a ROOT file

Newbie
1

___Hello everybody.
Is it possible to create a ROOT file in a program and read it in the same program?
I mean I create a ROOT file and fill it in the first part of program , can I read it in the second part of the same program?
Please read tips for efficient and successful posting and posting code

ROOT Version: Not Provided
Platform: Not Provided
Compiler: Not Provided

2

Obviously, see for example https://root.cern.ch/doc/master/tree1_8C.html

3

Thank you for your Guidance.