Why doesn't JQuery work after landing layout on Joomla?

Question

JavaScript

Made a layout. My layout has a responsive menu that works with jQuery. When I open a normal html file, everything works fine. Adaptability, deployment of a vertical menu - in general, everything works. But after "landing" this layout on CMS Joomla 3.7, the part that works with JQuery stopped working for me.

<script src="<?php echo $this->baseurl ?>/templates/<?php echo $this->template ?>/js/jquery-3.3.1.js"></script>
<script src="<?php echo $this->baseurl ?>/templates/<?php echo $this->template ?>/js/bootstrap.min.js"></script>
<script src="<?php echo $this->baseurl ?>/templates/<?php echo $this->template ?>/js/headhesive.min.js"></script>
<script src="<?php echo $this->baseurl ?>/templates/<?php echo $this->template ?>/js/script.js"></script>

PS: I tried to connect JQuery CDN, it did not give any results.
PS2: I wrote a test in the script.js file - it worked. JQuery is not working alert('hello');