What is the way to access the deep web?

The deep web is 98% of the internet. Facebook is a deep web website. For the other 2% get an onion torrent and a good vpn. But in reality seriously don’t. I’ve seen messed up stuff on the deep web. I can’t imagine what you’d find on there

you can access any Deep Web website using any web browser.
"Deep Web" is just a term used to describe websites that are not listed in google search results. they are intentionally "off-the-grid".
you can still view them if you know their addresses.
"Dark Web", on the other hand, consists of encrypted web sites, and requires special software to view.
this is not recommended, as there are many scammers there, because such sites cannot be traced...

The deep web is just pages that aren't indexed by search engines.

You probably meant the dark web, for which you should use the tor browser.
Then you visit the Hidden Wiki:
http://zqktlwiuavvvqqt4ybvgvi7tyo4hjl5xgfuvpdf6otjiycgwqbym2qad.onion/wiki/index.php/Main_Page

Tails Linux inside a virtual machine.

All I will say is that you need a certain browser in order to access to access the deep web. But the deep web is bad news. I won't go there for security reasons.