I wish to put Linux on my external hard drive via a USB stick

I have a hard drive I took out of another PC. I know I will need to format it in order to put the distro on it. Likewise, I have created a USB drive using etcher and have several distros burned on it. My question is since I plan to use all the drive for Linux can I skip the partitioning part of the installation? I get very confused when it comes to partitioning, and it is very difficult for me. Thanks.