Don't worry the categories are there. They just won't show up until there is a post in the caertogy.The other possibility is that you don't have the categories widget in your sidebar. You can go to Appearance / Widgets and drag the categories widget to your sidebar.
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Recent changes
Harsharose • 18 hours ago
Harsharose • 5 days ago
2607:FB90:EAC3:85A9:897A:CA2C:7CC3:E11B • 1 month ago
2403:5808:82EF:1:680D:6688:1FD3:3C6D • 2 months ago