Putting together your text and pictures tastefully is fun and rewarding.
For designing your book there are two programs which you might consider: Affinity Publisher & Blurb BookWright.
Suggest finding a book you love and examining its typefaces, spacing, graphical treatment, size and then apply some of those decisions to your book.
At the price of free is a program called BookWright from Blurb.com.
How to setup your book design document using BookWright from Blurb.com
A full-featured and professional level design layout program to a consider is Affinity Publisher. It has lots of features that at first you might not appreciate but later on you'll be thrilled they are there.
Setting up your design document in Affinity Publisher using Blurb.com margins, bleeds, and PDF export specs.
Note that to print a book a you need two design documents: one for the smaller inside pages and one for the larger cover jacket or image wrap.
Setting up Character and Paragraph Text Styles in Affinity Publisher will save you time and help you create a professional looking family history book.
How do you know what colors go together when you're designing your family history book? Check out this video on complimentary color theory and a free application you can use to get exactly the right colors.
Write a few paragraphs about the scene, place, and time for one of your characters. Perhaps what was going on in the news in the town where your mom was a kid. Or the political environment during your dad's career.
Post it in the Facebook Group.