Bazel has built-in support for remote execution, but you still need to write configuration to connect to EngFlow's remote execution service, and to make your builds compatible with remote execution. You can do this for a whole Bazel workspace, but might need to fine tune the configuration for certain types of actions and individual targets.
If you are setting up a Bazel project for the first time to work with EngFlow remote execution, start with Bazel First-Time Setup. You may also want to read Bazel Known Issues, especially if you are using an older version of Bazel.
If you are cross-compiling to a specific platform, need to change how a target is built, or change how a set of actions are run by the remote execution service, read Platform Options. You may also refer to Platform Options Reference for a full list of options recognized by EngFlow.