Help Me I’m Confused!!!!

Ok I decided to make myown website and i have used a program called trellix web to create it. I have not used html at all. I got it up and running and looking decent but now i decided i wanted to spice it up. I downloaded a program called J-Perk to put special effects on my site. I tried to put a color scroll on my site. I went to my file manager provided by my host and started looking through the files of html. My special effects program told me to copy and paste a code in the html but there are so many diff files i dont know which one to do it in and i dont know where to paste it to. If there is anyone that can help me please write me a message. or send me an email to ashlaroo@cs.com