Transfer code form previous CMS to WordPress

New to the wordpress world but so far im lovin it!

I had a website built by a friend of mine, and he coded it for his own CMS. Long story short the CMS crashed and before we could fix it, he dissappeared. Now im trying to take matters into my own hands and get the site back up on wordpress. I can see a lot of tags that just need to be modified for wordpress, but I know I wont see them all. Any suggestions for getting the code better suited for wordpress?

just for reference, the site is: https://tkimine.com/wordpress/

Thanks for any help!