Is it forbidden to decorate walls with fabric, whether it be an ornamental wall tapestry or any other ornamental fabric? And is painting on canvas and hanging it on walls permissible in Islam?

Covering walls and cladding them is reprehensible, but not forbidden. This is due to the extravagance and waste of money involved, unless there is a need for it, such as protection from heat or cold, or if it contains images of animate beings. In such cases, it is reprehensible to the point of being forbidden. As for hanging paintings on walls, drawing them is permissible as long as they do not include forbidden drawings, and acquiring them is prohibited if it involves extravagance.