An alternative is https://protonmail.uservoice.com and vote on what features you want Proton to work on.
This is the basic filter. No idea about sieve filters.
Using a browser
Left side scroll down to “labels” and hit the cog.
Again on the left hit “filters”.
Add filter, name the filter, hit next.
You can select subject, sender and 2 other options, add something to the box (perhaps the email you found in the header), hit next,
Now, decide where you want the email to go.
This site may help you pick a car without a full-time connection. https://vehicleprivacyreport.com/report/
You are most welcome.