Blog Layout and Search option

Site URL: http://themaplesquare.com

Hello Squarespace community,

I am about to go live with my website and love the look of it.
I have two questions which I hope are easy to resolve:

1. Can I change the layout of my blog page so it shows an unlimited number of blog posts as preview? It's currently limited to 20 posts per page but I'd prefer an infinite scroll.
2. How can I add a search bar at the top of the page into the main menu? My page will feature profiles of people and for each profile I am creating a blog post with an image, description and tags. I add tags to make the profiles searchable by topic but currently I haven't been able to add the search functionality.

Many thanks for your help
Eva