I just have a tip for you this time. I came across this when I was doing research for the previous question.
When you are composing an email message, if you are more comfortable with a list of your email addresses that you can just select recipients from,
tap the F9 key on your keyboard and a sidebar will appear with your address book.
Now, you can just click on a name, then click the “Add to” button at the bottom of the sidebar.
Once you have turned on the contacts sidebar, it will stay on in all future emails you compose until you tap F9 again which will turn it off.