Hi @Shruti1,
You can do so by updating the same of the sequence to be used in the main element of your schema.
Change pkSequence="XtkNewId" to pkSequence="<<your_custom_sequence_name>>".
However, you need to be careful while doing this on an existing schema. If your schema already has data and links to other tables using the auto-generated keys previously, doing this without due diligence might lead you into more issues. If it is so, then you should do an impact analysis and make a data strategy for doing this update on that schema.
For empty schemas, this should be a straightforward activity.
For new schemas, since last many builds, a custom sequence is automatically generated and used, unless some other settings override this feature.
BR,
Ishan