It’s a good idea to prepare your garden ahead of time so you are ready to plant when you arrive home. Mix compost into the area where you plan to plant, and dig the planting hole the approximate size of the roots. If you overestimate you can fill the hole with more soil later.
“Bare-root” plants are dormant (in a state of hibernation/rest) and usually don’t have leaves. Bare root plants can be found at nurseries and garden centers in large containers of sand. Once you choose your plant, a nurseryperson will wrap it for you in butcher paper with a piece of twine. I have seen bare root plants for sale that are already wrapped sitting out at some of the larger home improvement/gardening centers, but I don’t recommend you purchase these. It’s possible the roots have dried out while sitting in the bag and the health of the plant can’t be relied upon. If you do purchase one, save the receipt in case anything goes wrong later.
If you aren’t sure how deep to plant your bare root plants, ask a certified nurseryperson to show you before you leave the nursery. It’s important not to bury plants too deep or to plant them too high. Just as Goldilocks in the story of Goldilocks and the Three Bears you want to make sure everything is “just right.”