This blog will show you the REST API url which is used to get the document based on a specific version number.

To get the document based on version number:

https:///_api/web/folders/getbyurl(' ')/files/getbyurl('')/versions?$filter=VersionLabel eq ''

Inputs:

Parameter Value Example
<Folder URL> Document Library Name Documents
<File URL> File Name mydocument.docx
<Version No> Verion Number 1.0


Example:

https://sharepointsiteurl/_api/web/folders/getbyurl('Documents')/files/getbyurl('myfile.docx')/versions?$filter=VersionLabel eq '2.0'