Can not show full articles in blog page

It may be because of your theme.
Try to find out the excerpts hard coded inside the template

Thanks, but I would need more explanation, what file in what folder? what change?

The setting you changed was for your site’s RSS feed – not for the display of Posts on your site. In order to change the current display, You will need to start customising your theme’s template files via a child theme.

Leaf has his child-theme ready here
Then you must copy and change the file you are interested of into child theme. If you want modify homepage, the file is home.php
Find

<div class="entry-summary">
<?php echo '<p>' . wp_trim_words( get_the_excerpt(), 45, null ) . '</p>'; ?>
</div><!-- .entry-summary -->

and change with

<?php the_content (''); ?>

You can remove also

<p class="read-more-link"><a href="<?php the_permalink(); ?>"><?php _e( 'Full Article', 'leaf' ); ?> →</a></p>

Leaf home page is divided into sections, so you must act only where you need (not in slider, e.g.)

my site: mytoppet.com

This does not work for me. downloaded the child theme from here:
https://github.com/bradthomas127/leaf-child

It is called leaf-child-master.zip. I uploaded it via the appearance-theme function in wordpress, then activated it.

Then, I downloaded the home.php file from the original leaf folder.

I used Text edit to change the home.php by deleting

<div class=”entry-summary”>
<?php echo ‘<p>’ . wp_trim_words( get_the_excerpt(), 45, null ) . ‘</p>’; ?>
</div><!– .entry-summary –>

and adding:
<?php the_content (”); ?>

but you can see, it still says only part of the article…

OK, now I have another issue–which makes me wonder if this theme is simply not right for me–so it seems to take some of my text BUT it strips my formatting on the home page !!! In other words, I have an OL with li functions but it does not show it as a list…hmmmmm

First, I don’t think you removed at all <p class="read-more-link"><a href="<?php the_permalink(); ?>"><?php _e( 'Full Article', 'leaf' ); ?> →</a></p> because I see in your site “Full Article→”, and if you had removed those lines, those words wouldn’t be there, that’s for sure. Or, you did it in the wrong place.
Second, I said above: “Leaf home page is divided into sections, so you must act only where you need”. I see in your site that you have posts in categories and articles section, so you need to remove these lines from that sections, three times. I tested now and it works.
If I have to tell you how to take out word for word, based on the display you have now, here it is:
in Categories section remove:

<div class="entry-summary">
<?php echo '<p>' . wp_trim_words( get_the_excerpt(), 22, null ) . '</p>'; ?>
</div><!-- .entry-summary -->
<p class="read-more-link"><a href="<?php the_permalink(); ?>"><?php _e( 'Full Article', 'leaf'  ); ?> →</a></p>

and

<div class="entry-summary">
<?php echo '<p>' . wp_trim_words( get_the_excerpt(), 10, null ) . '</p>';?>
</div><!-- .entry-summary -->
<p class="read-more-link"><a href="<?php the_permalink(); ?>"><?php _e( 'Full Article', 'leaf'  ); ?> →</a></p>

Replace both with <?php the_content (''); ?>

in Articles Section remove:

<div class="entry-summary">
<?php echo '<p>' . wp_trim_words( get_the_excerpt(), 45, null ) . '</p>';?>
</div><!-- .entry-summary -->
<p class="read-more-link"><a href="<?php the_permalink(); ?>"><?php _e( 'Full Article', 'leaf'  ); ?> →</a></p>

and replace with <?php the_content (''); ?>

Last, excerpt always strips HTML.

tizz, thanks) tell me still please.
responsible for the main page file home.php
and which is responsible for the file category?

@userpress I’ve read some of your other posts and I usually can’t understand them.
Do you want to know which file is responsible for category archive pages?
Rephrase your question more clearly but please follow forum rules and open your own topic.