Weather in Alaska can vary.. especially in spring, so we suggest being prepared for a little rain, mud, and cold - with the possibility of sunny and 60 degrees. Mostly we recommend wearing shoes that are fine to walk around in outside and on uneven ground. If you're planning on wearing heels choose something blocky.
No, you will have to fly to Anchorage and then make your way to Seward by car, bus, or train.