Hi @Sannadi77
Try this way
In portal management:
1. Under Content Web Files > Hit New
2. Provide the name
3. Make sure your parent page is set to "Home"
4. Enter the partial URL just like the Name field.
Screenshot below for reference

To refer the image in the web template or in your HTML . Below is the reference

Either you can do an absolute path like my screenshot or do a relative path like "\image.jpg"
Note: Any image file formats are allowed
Hope it helps.
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