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How Do I Perform a Low Level Format on A IBM 5160XT

It completely depends on the disk controller you are using.

If you have the original IBM controller, you have to issue a "format-drive" command directly to the controller using a small assembly program entered in Debug (included with DOS). If it's a later 3rd party controller, then you can just run a routine in the ROM on the controller. This routine can also be run from Debug, usually with the single command of "g C800:0005", allthough the number (address) may vary depending on the controller you have.
I have dos 2.1 and can not find this DEBUG
On the command line, type "DIR /W" and it will show up in the list as DEBUG.EXE. It comes with all versions of DOS so it is suspicious if your disk doesn't have it. If it's not there, then you need to get it. You can use some other version than the one with 2.1 if you need to. There is a free one on this page but there are others.
ok I got it up now How do I tell what controller card I have?
Yes, the low-level format technique used depends on the type of controller.
Is there a manufacturer and model number on it?
If it's the original IBM supplied card, then you will see "IBM" and "XEBEC" on some of the chips.
Post a photo if you're unsure.
Here are pics of my floppy controller

how would I go about doing my low level format?


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Here are pics of my floppy controller

how would I go about doing my low level format?

Not the floppy controller. What we are talking about is the hard(/fixed)-disk controller. It should have one bigger and two smaller 2-pin wide connectors. The bigger connector should be connected to all the hard disks, while the smaller connectors should be connected to each their spesific drive. In the case you only have one hard-disk drive, one of the smaller connectors stays unconnected while the two other connectors are both connected to the one drive installed.
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sorry about that, I was thinking about another project here is the proper pics
of the hard disk controller

I thinks its an IBM


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Regarding the web page pointed to.

The G=C800:x method is not applicable in your case.

Because a third thread of yours suggests that you don't yet have the ability transfer software from the Internet to a 5.25" floppy, that rules out the ADVANCED DIAGNOSTICS floppy in the short term.

The 'Assembler code in Debug' section will work. The low-level format will take a few minutes to complete, and when complete, the drive's access light will go out, and the dash prompt will return in DEBUG.
can I have help on this
1. Boot from a DOS boot floppy that contains DEBUG.COM
2. Run DEBUG (you'll then see a dash prompt).
3. Enter the following (press ENTER key after each line):

a 100
mov ax,707
mov cx,1
mov dx,80
int 13
int 3

4. Press the ENTER key again. That will take DEBUG out of 'assemble' mode, and you'll see the dash prompt again.
5. Press the "g" key.

You should see the drive's access light come on solid.
I should have added this:

A statement in the 'Assembler code in Debug' section is, "This will format the drive as a 10MB drive (4 heads, about 306 sectors), with the original IBM controller."
That is correct for the original version of the IBM/Xebec controller - it only supported 10MB drives of type 1.
You have a later version of the controller, and it will be switched to support your 20MB drive. Accordingly, the code should low-level format your drive to 20MB.