How to edit text?

How do I edit the text? I've tried double-clicking and right-clicking, it doesn't work.

How do I edit the text? I've tried double-clicking and right-clicking, it doesn't work.

First of all, if this is a Da Vinci Resolve topic, please use the Da Vinci Resolve category and post there. It will more likely be answered.
Next, be clear as to what exactly you are trying to do, and how you are trying to do it. There's a lot of ways to edit text and double-clicking and right clicking is not enough information to go by as to what doesn't work.
Last, READ THE MANUAL!!! Watch the training videos.

Now, if you want to know how to add and edit text on a timeline in Resolve, one simple way is you can add a regular Text effect in the timeline. Then select the Text clip in the timeline and bring up the Inspector by clicking on it. That will show the Inspector. In the Inspector, you can type in the text, change the font, and make other changes on how the text is to display. By reading the manual, you will learn how to go about working with text on the Edit timeline.

I solved it. Why does my layout look different from most youtuber's layout?

There are almost an infinite number of ways to style your titles with a combination of font, color, size, and position, etc, it's up to you. Download the latest full manual which is for version 16 and go to page 805 for the section on titles.
I like quite simple ones. Pic shows the title plus the settings in the Inspector.

Title.jpg

Here's another one where each line has been sized differently.

Title2.jpg