What changes for golfers who are amputees?

Rule 25.3 covers players with limb deficiencies as well as those who have lost a limb:

• Prosthetic devices: using an artificial arm or leg is allowed if you have a medical reason and the Committee decides it gives no unfair advantage. You still mustn't use it in an abnormal way. Raise any doubt with the Committee as early as possible.
• Anchoring: if you can't hold and swing most of your clubs without anchoring because of limb deficiency or loss, you may anchor the club without penalty.
• Dropping, placing and replacing: you may give a general authorisation to any other person to do this for you, for the whole round.
• Replacing: you may replace the ball by hand or with another piece of equipment, such as rolling it into place with a club.

Source: Rules of Golf (2023), Rule 25.3.