Before your friends choose how to treat them, I suggest your friends pay attention to the following points in their daily lives:
First, wear shoes that squeeze your toes as little as possible, and wear shoes with wide sides, so that your toes have enough room to move and reduce further damage to your toes;
Secondly, we should choose suitable insoles specially designed for foot problems to reduce the stress of people's weight on soles and toes when standing and walking, reduce friction and relieve pain;
Third, we should always carry out proper activities on toes to promote blood circulation in the feet, so as to enhance the flexibility of toes.
I hope my answer can help your friend's illness!
The next step is to choose the appropriate appliance for correction. If necessary, you can consult me further.