@Alankrit-Choudhary Fork the lavender theme, go to the highlighted line in this file
And add {categories.posts.topic.title} inside whatever container, small, or h tags, or a P tag. Up to you I guess.
But do note that updates to the official lavender theme will require you to do some work to get them on your forked theme.
EDIT: If you want to make the title clickable, then you could do something like
<a href="{categories.posts.topic.slug}">{categories.posts.topic.title}</a>
Add small or span as neccessary...
