Change font type in posts

Hello, I’m using activello theme, but I would like to change my fonttype in written posts. How can I do that?

Hi there,
Thanks for reaching out.
In relation to your question here, could you kindly try out the following CSS code under the Appearance>Customize>Additional CSS section:

.entry-content p {
font-family: serif;

I hope this helps.
Best Regards,