This covers obtaining the ISO, connecting to Wi-Fi, partitioning, formatting, mounting, installing, setting up encryption and installing GRUB, in one article. Also includes some tips, like quickly mounting from install medium. Maybe this helps someone.
I wrote this more or less for fun; it is slightly more extensive than the installation guide geared for a more advanced setup. The wiki is mentioned in the article as well and is encouraged to be used too
AFAIK GRUB itself cannot be encrypted.
The Bootloader itself cannot be encrypted afaik, but the Kernel and initrd can reside on a LUKS Volume (GRUB_USE_CRYPTODISK). But, in order to prevent having to input your passphrase twice, you need to use a keyfile, and I have no experience with that, so I have gone another route. I don’t think that a kernel and initrd necessarily need to be encrypted