In the CSS, in section 3, scroll down to /* Genericons */.
Then scroll down farther until you find:
.entry-meta .author a:before {
content: "\f304";
Change to:
.entry-meta .author {
display: none;
That removes the author name.
Next go to:
.tags-links span + a:before {
content: "\f302";
Change to:
.tags-links {
display: none;
That removes the tags.
Oh, one more thing:
These changes may be overwritten if the theme is updated. If you don’t want to have to repeat this if the changes are overwritten, then you need to create a child theme and modify the CSS there.
The advantage to that is you will always have the original CSS to duplicate if you make a mistake.
