No startup Disk, OS X Base System, No Macintosh HD disk

What you’ve been told—option-command-R—is how to recover this.

Use macOS Recovery on an Intel-based Mac - Apple Support

Synopsis:

Using Disk Utility, select Show All Disks, and erase and reformat Apple SSD SM0256G Media device as GUID partitioning GPT and Apple APFS.

Then back out to the installer, and install Ventura on it.

Or bring it or send it into Apple.

Some YouTube video actually suggested Sierra here? A six-year old-operating system? One that predates the MacBook Air 2018-2020 series, and is thus incompatible with and will not boot this Mac?

What has already been suggested? Presumably booting Recovery, selecting Ventura? What happened with that?

Got backups? if so, restore those, and back out of whatever you’re trying with something as old as Sierra.

And you’ve presumably already then gone through the 🌎 ⚠️ won’t-boot-recovery section here, too:

… If you can't start up from macOS Recovery - Apple Support

My notes on error 5101...

Error 5101...

So, according to the articles, I have an incompatible Boot ROM version (or commonly known as BIOS). (To check it, go to the Apple logo - About My Mac- System Report - Hardware and see the number of Boot ROM version)

And that was right! I have two other MBPs and the Boot ROM versions were 428 for the 2014 and 424 for the 2015. The problem one was still at 192. My speculation is macOS has something similar to a compatibility mode so it could run on older BIOS versions but couldn’t boot from the Recovery Partition, especially Big Sur. I bought this Mac with no SSD and put in an SSD with Catalina pre installed, so the BIOS was probably not updated.

So how I solved this was pretty time consuming, but it worked! I used Shift Cmd Opt R to get Yosemite back on the SSD. Then I went to App Store and updated to Big Sur. After a longer than usual update and many more restarts that took about 3 hours total, my Boot ROM version was updated to 424 and the problem was solved.

EDIT: I got another one with ver. 180 firmware and when I trigger IR it doesn’t error out anymore, but the latest OS it could go up by IR is Catalina. From there I could manually update to Big Sur 11.1 but the firmware version stays the same. And of course, no access to Recovery partition. They fixed it in a half-assed way.

https://www.reddit.com/r/macbookrepair/comments/kab0an/error_5101f_on_macbook_pro_2015_and_how_i_solved/

Try this, I was also getting the same 5101F error..

pressing Option+Command+R doesn’t work so I reinstalled the earlier OS by pressing Shift+Option+Command+R and then Start button.

 It takes nearly 30-40 minutes to reinstall the earlier version of Mac OS. In my case I had Catalina installed by earlier version of Sierra installed.

 This will definitely work..

5101F error - Apple Community

MatthewAC wrote:

Yeah I've looked through all that, nothing worked for me.

Presumable SMC and NVRAM reset and the rest have all been suggested, and a bootable installer is either not available or not working.

Repeating everything already tried is futile, so send the Mac in.