The Implementation Governance Model is a framework that defines the roles, responsibilities, processes, and standards for governing the implementation of the target architecture. It ensures that a project transitioning into implementation also smoothly transitions into appropriate Architecture Governance, which is the practice of ensuring compliance with the enterprise architecture and its principles, standards, and goals. The Implementation Governance Model is part of the Implementation and Migration Plan, which is the output of Phase F: Migration Planning of the Architecture Development Method (ADM)12 References: 1: The TOGAF Standard, Version 9.2, Part II: Architecture Development Method (ADM), Chapter 21: Phase F: Migration Planning 2: The TOGAF Standard, Version 9.2, Part VI: Architecture Capability Framework, Chapter 50:
Architecture Governance

The purpose of the Architecture Roadmap is to provide a high-level view of how the Baseline Architecture will transition to the Target Architecture over time. It lists work packages on a timeline showing progress towards the Target Architecture, as well as dependencies, risks, and benefits. The Architecture Roadmap forms part of the Implementation and Migration Plan and guides the execution of the architecture projects.
References: https://pubs.opengroup.org/architecture/togaf9-doc/arch/chap20.html

The Architecture Landscape is a class of information within the Architecture Repository that shows an architectural view of the building blocks that are in use within the organization today (the Baseline Architecture), as well as those that are planned for the future (the Target Architecture). The Architecture Landscape typically contains a list of the applications in use within the enterprise, along with their relationships and dependencies, as well as other relevant architectural information. The Architecture Landscape helps to identify opportunities for re-use, consolidation, or retirement of existing applications, as well as gaps or overlaps in the current or future architecture.
The TOGAF Standard, Version 9.2, Part IV: Architecture Content Framework, Chapter 34: Architecture Landscape : The TOGAF Standard, Version 9.2, Part VI: Architecture Capability Framework, Chapter 47:
Architecture Repository