How to make normal text slide

As I see it, your only option apart from using a plugin, is to create a child theme, details here:
creating a child theme https://codex.www.ads-software.com/Child_Themes

And to put your code into the theme files.
– get your js file loaded in the page header
– add your css to your child theme’s style.css
Then either:
– locate your testimonial slider HTML in the chosen page template files
– put this HTML into a text widget

That seems like a pretty heavy task if you are not familiar with the code. I would consider changing your mind and go for a free plugin. There are quite a few of them available. I have recently used this one https://www.ads-software.com/plugins/testimonialslider/ – it’s pretty easy to work with.

i need show only text testimonials slider without any photos.

Well jeeva, I am sure that there are plugins that do testimonial sliders which don’t require images. If you won’t do a plugin, then I am afraid that I can’t help you, plugins are the WordPress way.

finally i found plugin “https://www.ads-software.com/plugins/content-text-slider-on-post/screenshots/”