Which order when refactoring ReactJs App (Starting with tests, hooks and redux)

I created a React Application. Now, time has come to start with refactoring and make it stable for the enhancements in the future. I would like to:

• Add tests (at the moment I do not have tests in my code)
• Switch to Hooks API (at the moment I use classes)
• Introduce Redux for state handling

Usually I would say, that it makes sense to start with a test-coverage and afterwards refactor with Hooks and Redux. But I am not sure, if the changes which comes with redux and hooks let me still make use of the test-cases or if I have to rewrite a large part of the tests.

In which order would you introduce these three basic changes?

Thanks a lot