RAD Studio 10.4 shipped with InterBase 2020 Update 1 embedded versions. IBLite and IBToGo are technically the same binary with different features -- encryption support, database size, etc -- enabled based on the license, with Enterprise and Architect editions of RAD Studio including the ToGo license for mobile.
InterBase embedded versions offer a high performance database that you can deploy with your applications on all platforms supported by RAD Studio, and of course also a more powerful InterBase server version that you can also deploy to customers via a VAR agreement.
In terms of installation, IBLite and IBToGo are not optional add ins, but they are a required package part of the core installation.
More recently, the InterBase team refreshed the build, mostly to fix an issue on macOS. Given we don't update the core installation (not until 10.4.1, at least) we have made the new package available in GetIt. When you install it, you update the InterBase embedded binaries.
To install, open the GetIt Package Manger and search for it, for example typing "togo":
Install it, accepting the installation, and it will proceed to download and install the package, asking to restart RAD Studio at the end of the process: