Hi adwebcom1,
You can add the following CSS code to the Backend > systems > Site Templates Style > Ja blockk - default > Tools Custom CSS:
.item-page .com-content-article__body > p:first-child::first-letter, .item-page .com-content-article__body p.has-letter::first-letter {
color: var(--body-text-color);
font-size: var(--h5-font-size);
font-weight: normal;
padding: 0;
margin: 0;
line-height: 1.778;
}