Software Requirements Specification (SRS) documentation Writer

I give you a web admin panel and mobile application login, according to that software development specification full/complete document has to be made. All the features that should be included in that

We are looking for a full/complete Software Requirements Specification (SRS) documentation, Software Design Specification (SDS) documentation with UML, ERD, Use Case, Sequence, Flow, etc. diagrams, screen mock-ups and mobile app & full back end including administration, storage, api's, security, data protection, etc.

but they have to be documented in a proper manner.

You should be aware of CMMI level documentation practices.