The supported environments for all of the available versions of ALM can be found here:
Alm 12.55 is covered under the ALM12.5x versions compatibility matrix for the user client systems and the Application server environment.
As of yet there are no patches for the ALM12.55 version only the initial release version. In the future when patches are released they will require an uninstall of the prior version and reinstall of the patch version unlike in the past where the patches were installed onto the current version (this change was implement since ALM12.2x and because of the nature of it, all patch versions are also a full version allowing one to install directly from the patch and be current with all cumulative information rollled into the patch thus saving steps during the implementation.
Hope this helps,