Hi, Go to Edit HTML and add this code just before </head> tag of your blog:

<style type='text/css'>
blockquote{border:5px solid #888;padding:1.5em;}
</style>

Thanks

How can I change the solid line of a blockquote to a box blockquote? I tried to add it in to 'Add CSS', doesn't allow. I did purchase the pro version.

Hi, follow this: https://newbloggerthemes.com/blog/remove-blogger-auto-read-more/

find this:

body,
button,
input,
select,
textarea {
color: #333;
font-family: Lusitana, "Times New Roman", serif;
font-size: 16px;
font-size: 1.6rem;
line-height: 1.5;
background-color:#f8f4ee;
}

change "Lusitana" font to other.

please follow the instructions given.