@edvinaspauza you can make a child theme as per recommended by @mr. Lou, but don’t remove the entire code. you need the first and last closing div.
Just remove:
<footer id="colophon" class="site-footer" role="contentinfo">
<div class="site-info">
<?php do_action( 'bold_headline_credits' ); ?>
<a href="https://www.ads-software.com/" title="<?php esc_attr_e( 'A Semantic Personal Publishing Platform', 'bold_headline' ); ?>" rel="generator"><?php printf( __( 'Proudly powered by %s', 'bold_headline' ), 'WordPress' ); ?></a>
<span class="sep"> | </span>
<?php printf( __( 'Theme: %1$s by %2$s.', 'bold_headline' ), 'Bold Headline', '<a href="https://bluelimemedia.com/" rel="designer">Bluelime Media</a>' ); ?>
</div><!-- .site-info -->
</footer><!-- #colophon -->
If you want to simply hide it with CSS, you can use:
.site-footer {display: none;}