You need to place the PHP code in your theme as stated in the instructions https://ww.wp.xz.cn/plugins/wp-pagenavi/installation/
If you are not sure where to place it, please contact your theme author.
but were in style.css or function.php?
Ok, I have in index.php
<div class=”navigation”>
<div class=”alignleft”><?php previous_posts_link(‘« Previous Posts’) ?></div>
<div class=”alignright”><?php next_posts_link(‘Next Posts »’,”) ?></div>
</div>
Ok I habe about 400 posts in multipage….
<div class=”navigation”>
<div class=”alignleft”><?php previous_posts_link(‘« Previous Posts’) ?></div>
<div class=”alignright”><?php next_posts_link(‘Next Posts »’,”) ?></div>
</div>
I must replace with multipage code?