Old coins are usually in:
1, antique market, now basically every city has one or several antique markets, you can have a look if you want to sell them.
2. Gift companies specialize in making commemorative books with commemorative coins and banknotes, but such companies have requirements on quantity and appearance.
3, online channels, with the recent increase in online shopping this year, many collectors have also appeared in online channels to buy cents.
4. banks. Banks are the safest places to issue and recycle coins. But it can only be exchanged at the original price, and it is not recommended to go.