Before you rush to install the public beta of Catalina, be aware that the Sims 4 does not currently run in this new OS. This is because of the ActivationUI file which is still 32-bit and 32-bit is no longer supported. EA fixed this in the April ’19 patch but unfortunately had to roll it back in the subsequent hot fix patch as it rendered the game unplayable for all users running 10.7 Lion..

If you are desperate to install a beta version of the operating system on your Mac then make sure to install Mojave on an external drive or install a VM so you can still play Sims 4 and 32-bit apps.