My wife and I are not divorced officially paperwork has been filed. How do I apply this to my tax return. I don't have all her personal info such as SSN

[MarilynG1]

If you were still married on December 31, 2023, you can file as Married Filing Separately, or as Head of Household if you have dependents. 

All you need is her name and SSN for your MFS return.  She will need the same from you, so civil cooperation is necessary if you both want to Efile.

You can mail your return without her SSN.  If you filed a joint return in the past, you can get a tax transcript from the IRS that will have her SSN.

Here's more info on Filing Status.