Hello!
In this case you need to download Your theme.
Then edit file loop.hbs
Then add under this lane:
<h2 class="gh-card-title">{{title}}</h2>
Somethink like that:
{{#if tags}}
{{#foreach tags}}
<a href="{{url}}" title="{{name}}">{{name}}</a>
{{/foreach}}
{{/if}}
That’s give you tags under title, remember that you need to style it!
Then you need to edit post.hbs like @Cathy_Sarisky said and find:
{{#if primary_tag}}
<a class="gh-article-tag" href="{{primary_tag.url}}" style="--tag-color: {{primary_tag.accent_color}}">{{primary_tag.name}}</a>
{{/if}}
Then edit this like previous:
{{#if tags}}
{{#foreach tags}}
<a href="{{url}}" title="{{name}}" class="gh-article-tag tag tag-{{id}} {{slug}}">{{name}}</a>
{{/foreach}}
{{/if}}
Also have on mind that you need to make css style for it ;)
Then make .zip file and upload theme on Your ghost instance.