Should our normal user do preparation for the hard fork?

for example, backup the wallets, anything else we need to do before and after the hard fork?

What hard fork?,

Overwinter is a hard fork:

@lyhistory if you are running a full node, a backup of the wallet.dat is a good idea but not 100% necessary. Be sure you are on 1.1.0 or later and keep the node running during the fork to help propagate the new rules.

cool, yes, I backed up everything, wallet and private key, I’ll keep the node running on my laptop overnight to give my support