How to change the prompt line and why the arrows do not scroll through the history?

Question

linux

The following instruction worked:
1. create a user:
useradd -m username
2. set the password password
passwd username
3. remove it from sudo (must!):
gpasswd -d username sudo
4. add it to the www-data group
gpasswd -a username www-data
The user has been created, everything is fine, but the prompt line is now just $ and export PS1= 'what I want' does not help - it still remains $
And second: the arrows do not scroll the history, but drop out to the console ^[[A, for example .
WHAT?

Answer 1

It was the default in Debano distributions other than bash.
Change shell.
And for the future it is necessary to fulfill

sed -ri 's|SHELL=/bin/sh|SHELL=/bin/bash|' /etc/default/useradd