Heading on blog posts overlapping

I don’t understand why you’re using this CSS with an elementor block:

.elementor-1625 .elementor-element.elementor-element-22ac426 .elementor-heading-title {
   line-height: 0.1em;
}

The fix is to use

.elementor-1625 .elementor-element.elementor-element-22ac426 .elementor-heading-title {
   line-height: 1.2 !important;
}

To add or override CSS: use the “Additional CSS” option in the customizer. https://codex.wordpress.org/CSS#Custom_CSS_in_WordPress

Learn to use the Chrome Developer Tools or Firefox Developer Tools to help you see and test changes to your CSS.

However, you should probably go back to your elementor settings and do it correctly in the first place.