External Hard Drives back up and working drives

A good reliable backup of images only needs to be done once because Lightroom doesn't touch the images. The import process is simply a process of copying the images to the drive and adding them to the catalog, which is a database. After that, all the adjustments, cropping, adding to the collections, keywording, everything you do in Lightroom is simply working with that catalog. So if you ensure that the images are backed up securely by whatever means you are confident with, it is then critical to ensure that the catalog is backed up on a regular basis. That could be daily, every time Lightroom closes, weekly, whatever you choose. And the backup needs to be directed to a folder on the drive other than where the original catalog operates. Otherwise, if that hard drive crashes and that is where the backup is located, you are out of luck.

Besides backing up to external hard drives, you might consider looking into cloud services such as Google Drive, for example. Utilizing such as service places client images and other valuable images off site in case of some unexpected disaster that could destroy even a carefully stored external device. Google Drive is only one suggestion, there are many such services available.

I have always just literally copied and pasted the whole drive to each back up. So my first question is... is this the best way to do that?

Are you talking about Lightroom Classic? If so, the above is not the best way, it is not even a good way to do this. What you really need is third party backup software that can make automated backups at some regular frequency (daily, weekly, whatever you feel is appropriate) without human intervention. Why is this necessary? Because humans doing the backup has all the problems associated with human beings, that humans can forget, humans can be too busy, humans can be lazy, etc. and then the backup doesn't get done, and that increases the risk that you will lose work. NOTE: Lightroom Classic has a feature that allows you to make a regular and automated backup of your catalog file on a separate hard disk, you should definitely turn this on; but this feature does not make backups of your photos and does not make backups of your custom presets.

secondly, I now want have like working drive but only have like the one folder I'm working on available, is there a way to do that?

I have no idea what you mean by "available". The only method I would recommend is to import your photos into Lightroom Classic and then DO NOT DELETE them from Lightroom Classic, unless these are clearly unusable (out of focus, horribly underexposed, horribly overexposed, etc.). All of your editing work, plus user provided metadata (captions, titles, keywords, etc.) are in your Lightroom Classic catalog, and deleting the photos from the catalog means that you lose this work, the work is gone. Don't do this.

Working with Lightroom Classic, it's always a good idea to have a backup of your images on a separate hard drive. The method you choose for creating that backup is up to you because Lightroom doesn't create any backup of the images. But just as importantly, you need to have a backup of the catalog because that file is what contains all of the adjustments you have made to those images. Lightroom Classic (or even Lightroom for the cloud for that matter) doesn't touch the images. They always remain in their pristine state. So it's critical to have backups of the catalog stored separately from the images and separately from the hard drive where the catalog is operating from.