Use Standard formatting, unless otherwise specified. Open the paragraph tab. Double space, no spaces before or after a paragraph, indent paragraph 1st line: 0.5, alignment: left (NOT justified), outline level: body text.
Chapter breaks – use a hard page break. Come down 5 or 6 ds lines, type chapter and title if wanted. Then come down another 3 or 4 lines and begin the text again.
One space at the end of sentences. 2 spaces was standard years ago, and a lot of authors still use it in their manuscripts. But most publishers now require 1 or they don’t mind it.