Need help building/fixing an already existing slideshow

I have add the slide show functions in my project. By the way, the arrows are not showing nor working, and also be able to use the arrow keys on the keyboard. The height of the images are different between each other and it keep shifting throughout the photos. I would like to have equal height, if that’s possible. I used an already existing slideshow template called Slick Slider ([login to view URL]) and the one that I used is called FADE, you just need to scroll down a little to find it. You can create a new slideshow or fix the code, if you would like. Totally up to you. For reference, I mentioned this website in the freelance job [login to view URL] (it has two photos at the same time but it’s meant to have only one at a time). You can also check this one for reference [login to view URL]