Try out the free versions of the apps and decide whether you would pay for at least two of them.
Since I already use other alternatives like Bitwarden for many of Proton’s services, I’m only using Proton Mail and I can’t justify subscribing to Proton Unlimited until they release a Linux desktop client for Proton Drive.
Vote here and leave a message to let Proton know how important a Linux client for Proton Drive is.