Too many wrongs with them... By the way; for 3) anything you do to a text layer (except editing the text) changes it to a bitmap layer. If you want to do it explicitly (but why?) right-click and "Discard text information". For this logo I would have used:
- Create "GP" text layer and position
- Layer>Text>Text to path
- Shear path using Shear tool in Path mode
- Select>All, Select>Shrink (width of square), Select>Invert
- Open Path list, RIght click path, and "Add to selection"
- Add transparent layer
- Make the gradient by drag the the Blend tool across the while image
- Make the "Gimp 2.10" text layer
- Set alpha-lock on layer
- Select>None and make the gradient by dragging the Blend tool
- Layer>New from visible
- Filter>Blur>Gaussian blur
- Move to bottom, reduce opacity and shift