Really don't know where to go from here - a few questions ...

9AmberMoog - you can install 1Password without adding anything else to it. But if by "extensions" you mean the 1Password browser extension for Safari, I would strongly suggest you not attempt to use 1Password without installing 1Password for Safari. Reason? Because you won't be able to auto-fill any of your login items into websites where you have accounts, unless you manually copy/paste both the username/email address and the password for the site from 1Password into the browser. You can do this, but it's considerably more work and it leaves your password copied to your system clipboard (and thus available to any other process on your Mac until it's removed or you copy something else). Can I ask why you want to do that?

Regarding "offline," if what you mean there is: can you access your 1Password data when you aren't connected to the internet, yes. Every 1Password app stores a local cache of your data that you can unlock (decrypt) with your Account Password even when you're offline.

Regarding the 1Password for Safari extension, click Safari > Settings from the menubar (or type ⌘ + ,) to open Safari Preferences, then click the "Extensions" tab. Do you see 1Password for Safari in the left sidebar? Is the box next to it checked? If not, check that box. If it's not there at all, you can reinstall at this link.

I'm not sure what tutorial you may have watched or how long ago, but support.1password.com has many how-to pages and videos. The Getting Started page is, well, a good place to start. 😃