i cant find my machintosh hd in disk utility

MacOS Base system is the minimal MacOS system from an Installer image. It is about 5GB in size, more or less.

What is the size of everything on that drive?

If it is around 5GB, you have likely written over the previous contents of your drive with this. Recovery from a spinning magnetic drive would be extremely tedious. Recovery from an SDD drive is out of the question.

If the size of everything on the drive is over 30GB, you may not have lost everything --yet. Attempting a Recovery would take getting a different drive, in an External enclosure, Installing MacOS on the drive in the external enclosure, and running MacOS and additional Utilities such as Prosoft Data Rescue to attempt to salvage the data.

To make progress, you should obtain an additional drive, a candidate for replacing your Internal drive, and an external enclosure or adapter to connect it temporarily (not an all-in-one drive in an enclosure that cannot be removed).

Connect it to your Mac and use it to install MacOS on the new drive in the external enclosure. Boot from it and run it for a while.

If all seems ok, you may want to swap it inside your Mac to regain portability, and put the old drive in the enclosure or adapter. But there is no rush to do so.

Once you have a working MacOS, you can try to examine the old drive and see if files can be salvaged. You can use additional tools as well.

Be on the alert for problems cause by internal SATA cable failure. In some MacBooks, it is thought that abrasion against the rough inside of the metal case erodes the insulation and causes short circuits.

Then that may just be showing a failed Install, that has not over-written anything yet.

Can you start up from that drive using Alt/Option at startup?

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Here is the rough timetable of when Installer begins to over-write things:

start download from Mac app store. This takes 20 minutes to an hour.

Once complete, start Installer. You specify disk on which to Install.

Install checks things out and then copies (adds) MacOS Base system to the destination drive. Time 20 minutes to as much as 3/4 hour if your drive is slow.

Installer sets startup to the new MacOS Base System and does a Restart.

>> a failure right here means you still have everything on your old drive, (plus about 6GB of MacOS Base system that does not work)

ONLY if Restart was successful do you begin replacing files to move to the new version of macOS. Time 30 minutes to 3/4 hour.

Restart again and comes up running the new version, in Setup Assistant.

if you have drive view enabled, and your drive can not tell Disk Utility it make&model, and a reasonable non-zero capacity/size, any drives not showing have died. They cannot be erased, formatted, repaired, or used unless they show up with their proper credentials.

Oh, that is Bad news. You have only 1.55GB of data on that drive, not even a complete MacOS Base System.

Use the View button in the top left to make sure you have the widest view of everything on your Mac. (It may be device View).

DO NOT Erase your Backup drive or Install on that drive. You may be really glad you have something there, and using it for other things could wreck it, leaving you with nothing.

A new drive in an enclosure can be had for well under US$100, if you don't have a spare one on hand.