Install Bash by running the following commands:
./configure --prefix=/usr --with-curses &&
make &&
make install &&
logout
Replace the static bash with the dynamic bash and re-enter the chroot'ed environment by running:
mv $LFS/usr/bin/bash $LFS/usr/bin/bashbug $LFS/bin &&
chroot $LFS /usr/bin/env -i HOME=/root /bin/bash --login
The Bash package contains the bash program
Bash is the Bourne-Again SHell, which is a widely used command interpreter on Unix systems. Bash is a program that reads from standard input, the keyboard. You type something and the program will evaluate what you have typed and do something with it, like running a program.