html splash page

hello!

I have sliced template exported with photoshop as html and images and I want to set this html page as my splash page.

https://www.elegantthemes.com/forum/download/file.php?id=62643

I want that click on MESTO MEDZEV will redirecting you to my wordpress page https://www.medzev.info.
Linking in html is no problem for me, but I wondering how to set wordpress redirections easy and correctly.

Where should I upload folder and html file? In main ftp directory or theme directory? And how to set wordpress that this splash page can be seen only first time when someone visit https://www.medzev.info?

thanks for reply!