Is alopecia areata treatment necessary? Are there any home care ampoules?

I recently noticed a circular patch of hair loss on one side of my head, and I think it's alopecia areata. I've heard that regular hair loss can be managed with medication or shampoo, but I've heard that alopecia areata requires a different treatment approach.

What I'm curious about is the treatment method.
Is it necessary to receive injections or other treatments for alopecia areata? If the area of ​​hair loss is small, I'm wondering if other treatments, such as medication or ointments, are possible.
If I need treatment, what is the process, how long does it take, and what are the chances that hair loss will recur after treatment?

Inquiries about home care products
There are also questions about home care products that can be used daily at home.
Could you recommend any functional ampoules or supplements specifically designed to help with hair growth in alopecia areata?