Group And Ungroup Rows

Hello,
in my sheets there are a lot of projects, organized by 3 levels :
Level 0 : project
Level 1 : activity of project
Level 2 : sub activity

See image : Cattura.PNG

I would like to have a small group button (the small +) to the left of each level 0 (project). When i press it, all activities and relative sub-activities must be grouped under the project row and obviously vice-versa, ungroup.

Welcome to the forum

Please attach a sample workbook (not a picture or pasted copy). Make sure there is just enough data to demonstrate your need. Include a BEFORE sheet and an AFTER sheet in the workbook if needed to show the process you're trying to complete or automate. Make sure your desired results are shown, mock them up manually if necessary.

Remember to desensitize the data.

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