try a 3 block table and your text in the centre
add
.body {
font-weight: 400;
font-style: normal;
letter-spacing: 0px;
line-height: 1.4em;
}
to your custom css

Hello

You may also wish to experiment with the Layout -> Options -> Template Width field of your template style settings. This field will only effect the content width of your template.

Ciaran

hi. i want to only oondent the paragraph text and keep the heading and template width normal width.

just like this example https://drcarolineboyd.c o m

any idea how that was done?

Hello

There is a number of ways of doing this. As you do not appear to be using the Joomla article titles, you could try something like this (custom css)...

.maincontent p {

    max-width: 700px;

    margin-inline: auto;

    text-align: center;

}

This will put a max-width and center all paragraphs within the content area.

Ciaran