In the current explanation for Enable NSG flow log, steps 10 and 11 seem to be outdated. The current version doesn't have any retention settings available anymore.
See current Portal screenshot:

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@ashemedai, Thanks for your feedback. We are looking into this query and will update you as soon as possible.
@ashemedai, Yes, It looks like the document has to be updated. Previously you can set log retention policy from 1 day to 2147483647 days. If a retention policy is not set, the logs are maintained forever.
Now choosing on retention policy might be eliminated and logs will be stored indefinitely. Let me check with the team once before committing the PR. Appreciate your feedback.
@ashemedai, Appreciate your patience. The team is working on fixing the document and it will take some time for the changes to get reflected.
We are closing this issue for now. If there are further questions regarding this matter, please reply and we will gladly continue the discussion.
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@ashemedai, Appreciate your patience. The team is working on fixing the document and it will take some time for the changes to get reflected.
We are closing this issue for now. If there are further questions regarding this matter, please reply and we will gladly continue the discussion.