Hello @aaedla,
Hope you are doing good.
Hope you have followed below steps
1. Navigate to https://make.powerapps.com
2. Select the respective Environments
3. Expand Dataverse
4. Select Tables
5. Open the Table where you want to enable attachment
6. Click Three dots and select Settings

7. Make Sure Notes and Attachments is selected

If all above steps already Done and it still not displaying the Form then follow below steps
1. Navigate to https://make.powerapps.com
2. Select the respective Environments
3. Expand Dataverse
4. Select Tables
5. Open the Table where you want to enable attachment
6. Click Forms and Select Information Form
7. Add a Form then Click Components then Select TimeLine

8. Just Drag and Drop Timeline into the Form

If you want to Have only Image field then Create an Image field

That's it 🙂 Hope this helps
Please mark as Answer if it is helpful and provide Kudos
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