Should I export BOTH Photos and iPhoto libraries to my new external hard drive?

I have a new external hard drive and am learning how, and preparing to export, ALL photos and videos to that external hard drive. (I have already done a Time Machine back-up on my separate external hard drive.)

I see that there are two seperate Libraries in my Pictures Folder: Photos Library and iPhoto Library. I've read the information about how they are the same pictures but just identified in different places or whatever (sorry, I am quite the layman) but should I, in fact, just transfer BOTH libraries?

I may, or would like to, remove all the photos from my ageing MacBook Pro to save space so it's important I make sure I have these photos as proper files, elsewhere anyhow.

Thank you. Hoping for advice.