How can I make sure rain doesn’t get in the front door?
Double exterior doors that open inward are notoriously difficult to weatherproof, as wind and rain push against the doors in the same direction they should be opened. If you see water seeping in under the doors, check to see if it’s coming in below the threshold. This may mean that the sealant was not properly applied when the threshold was installed. To fix that, cut the sill in the middle so you can pull it out laterally in two parts. Then replace the threshold. The type with metal on the outside, but a wooden insert on the inside and a wooden top, which looks like you have it, is better than an all-metal threshold, which gets so cold that condensation – and eventually mold – is likely to form on the inner surface during winter.