Why not use Firefox Relay? It’s a mail forwarding service with 5 aliases in the free version, and unlimited in paid. I’m using that in combination with my gmail account and it works beautifully.
If you only occasionally need a vpn, the free tier in proton is probably sufficient (but you can’t select servers, they will be assigned at random), and you could use windscribe as a backup (you can select servers in the free tier yourself, but traffic is limited to 10GB per 30 days).