That's the beauty of lemmy and other open protocols, you can experience it however you like. If you prefer the stock web experience, it's there, if you prefer an alternative web experience, it's there, if you prefer an app, there are several to choose from. If you don't like any of that, you can even spend some time and make your own crazy thing.
Brave Browser + uBlock Origin (for PC) Jerboa (for Mobile)
I mean, you don't really need any addons if you're using the lemmy web, so I'd recommend going with addon-less bromite or "Webapps" from F-droid so u get better performance
On iOS Memmy is a really good app given how new it is. Just found out about Bean which is really impressive for just entering TestFlight.