Buddy wants to make a wedding registry site using a Themeforest theme. How do we start?

I went through the forum a little bit and all of this is REALLY complicated for someone as computer illiterate as me. I checked out the tutorials but all of them seem way more complicated than I was anticipating or are addressing things way deeper than what I think we need? (Not sure). Is there a good one to get started with for something as simple as this?

My buddy found a nice theme on themeforest- and wants to make a wedding registry site that we can put up for like, 4 months or so before his wedding. It’ll have the information, the gifts registry, guest signing stuff, etc.

Here’s what I know:
We’ll need a website address that’ll be easy to get. So no help needed there.
We’re gunna get a host- I was thinking Bluehost? Though if there is a good host that works with ya’ll better… Lol
Would we just purchase the theme and then input it into the “website building” section of the host then at that point? Or is there a special template to work with like wordpress style templates? And edit the html of it in sections that are relevant?

It won’t be a problem to find the theme but make sure it comes with the features all you need.

You’re good way to start…