Doubled Disk Volume and Other volume in Container after erasing the disk and installing the OS

If there is no data on the computer of any importance, run recovery and use DIsk Utility in Recovery to View menu -> Show all volumes. Then reformat the top most listed volume completely. Then install the operating system. The problem is you formatted a container of the volume, and not the entire volume. When you format the entire drive, it still creates a recovery volume, but it does not take as much space as when it is separated.

It is probably best & easiest just to start over again by following @a brody's instructions. In fact that is probably a good time to install macOS Catalina, but you may want to create a bootable macOS 10.15 USB installer while you are able to boot macOS. FYI, your laptop also supports the most recent version of macOS which is macOS 12.x Monterey although next week I believe macOS 13.x Ventura will be officially released, although I suggest avoiding Ventura for at least several months until Apple resolves all of the outstanding bug fixes which seem to always be necessary after Apple launches a new OS.

How to create a bootable installer for macOS - Apple Support

If you only have a 120GB SSD in the laptop, then performing a clean install with the latest OS is the best choice, otherwise you will run into the same issue of running out of storage space the next time you attempt to upgrade macOS to a newer version since your drive is filled with data. Right now with a clean install of macOS the drive is empty except for the OS itself. Just something to consider.

FYI, I think you mixed up the two operating systems. Catalina is the newer OS. macOS Catalina introduced a new drive layout consisting of multiple new APFS volumes. The traditional "Macintosh HD" volume is still there, but now it is a read-only volume consisting of the macOS system files. The new "Macintosh HD - Data" volume (or "Data") volume is a new APFS volume containing the home user folders containing user data and also some system preference files which need to be modifiable by residing on a read+write "Data" volume. There is also a new APFS "Update" volume used to apply macOS system updates. Older versions of macOS can see these new volumes, but will get confused by them and may even send you an alert about a problem with the "Update" volume because older versions of macOS don't know what to do with it. Here are a couple of Apple articles about the changes to the drive layout for macOS 10.15+:

About the read-only system volume in macOS Catalina - Apple Support (CA)

Signed system volume security in iOS, iPadOS, and macOS - Apple Support

Edit: You should always have at least 20GB+ of free storage available at all times for the normal operation of macOS. Keep in mind that even 20GB of free space can quickly disappear due to the cache & temp files utilized by your apps and macOS. Some workloads may require even more free storage space.

If you cannot maintain at least 20GB+ of free storage space, then you should consider replacing the SSD with a larger OWC Aura SSD which is a third party SSD which will fit the Apple proprietary SSD connector.

However, you will want to keep the original Apple OEM SSD because macOS 12.x+ installers will require the original Apple OEM SSD to be installed internally when installing macOS 12.x+ for the first time. When installing macOS 12.x+ for the first time, the macOS 12.x+ installers will refuse to install a system firmware update while a third party internal SSD is installed. After macOS 12.x installs and the system firmware has been updated, then you can reinstall the third party SSD and install Monterey to it. You will likely need to repeat this process again when upgrading to macOS 13 Ventura for the first time as well.