Here are a few free e-books that can be really useful when selecting your cloud migration strategy and when migrating your resources to Azure. They will give you a nice overview of tools, solutions and design strategies.
Cloud Migration Strategies E-Book - selecting the right strategy can have a huge impact on the financial aspect of your cloud usage and the migration success rate.
Cloud Migration Simplified E-Book - this book will help you learn how to apply best practices for your successful migration, as well as the tools that are provided by Microsoft or it’s partners.
Azure Migrate E-Book - discover, assess and migrate infrastructure, applications, and data to the cloud with Azure Migrate.
Cloud Migration Essentials E-Book - discover, execute migration, and optimize your cloud services and resources.
Designing Your Hybrid Cloud Strategy E-Book - accelerate your migration using the right tools and with limited impact to your business.
Also, don’t forget to check out this MS Learn path related to Azure Migrate: Virtual Machine Migration Learning Path
I hope this was helpful. Good luck with your journey to the cloud.