Use a Background: section. Here is an example.
EDIT: the variable if in the Background: will be re-initialized for every scenario which is standard testing framework “set up” behavior. You can use hooks such as callonce – if you want the initialization to happen only once.
If you are trying to modify a variable in one scenario and expect it to be now having that modified value when the next Scenario starts, you have misunderstood the concept of a Scenario. Just combine your steps into one Scenario, because think about it: that is the “flow” you are trying to test.
Each Scenario should be able to run stand-alone. In the future the execution order of Scenario-s could even be random or run in parallel.
Another way to explain this is – if you comment out one Scenario other ones should continue to work.
Please don’t think of the Scenario as a way to “document” the important parts of your test. You can always use comments (e.g. # foo bar). Some teams assume that each HTTP “end point” should live in a separate Scenario – but this is absolutely not recommended. Look at the Hello World example itself, it deliberately shows 2 calls, a POST and a GET !
You can easily re-use code using call so you should not be worrying about whether code-duplication will be an issue.
Also – it is fine to have some code duplication, if it makes the flow easier to read. See this answer for details – and also read this article by Google.
EDIT: if you would like to read another answer that answers a similar question: https://stackoverflow.com/a/59433600/143475