Answer your question based on my experience and experience.
The first question: Of course it’s not “very different”. Calligraphy is the basis of seal cutting. Calligraphy and seal cutting both use Chinese characters as expression objects (seal cutting also has portrait seals). Many seal cutting masters in the history of Chinese art are also famous calligraphers, such as Wu Changshuo, Sha Menghai, etc. However, seal cutting does have its unique features, because the text form it expresses and the tools it uses are self-contained, so it has its own unique charm and artistic difficulty.
The second question: How to get started: 1. Apprenticeship (you can take specialized classes for a fee; there are often elective courses in seal cutting in universities) 2. Self-study (recommended books: Introduction: Deng Sanmu's " Seal Engraving Science"; Introduction Series: Shanghai Painting and Calligraphy Publishing House Seal Engraving Introduction Series; Famous Seals: Han Seals, Xiling Four Seals, Wu Changshuo, Qi Baishi and other masters' seals.
The third question: Tools. The basic ones include: seal engraving dictionary, carving knife, printing bed, sealing stone, sealing pad, rubbing paper (special rubbing paper), rubbing bag (for edge rubbing), and sandpaper. See the second question for information books.