3rd Party (?) Lens recommendations for a7R IV Please

[Stargirl71]

Hi everyone!

Not sure if I should post here or in Gear under Lenses?!

Newbie/beginner here so I'm really REALLY new to the technical side of things
I was super lucky to receive a Sony A7R IV for my birthday recently, which was amazing but also a little daunting - plus represents a pretty steep learning curve (aka jumping in at the deep end!) TBH I was expecting something a bit more mid-range lol. Not that I'm complaining

So I need lenses, obviously...and I have zero idea really what to look at in this respect. I don't think I can afford anything much from the Sony range (not the high-end stuff anyway) so I've been researching some of the 3rd party options. My (limited) understanding is that to utilise the full potential of this particular camera I have to have lenses that are capable of doing that.

My interests are largely landscape/outdoors/nature and I'm super keen to get into night/astro photography. I won't be doing much in the way of action/sports or portrait work.

I'd be super grateful if anyone can give me some advice/suggestions (also, EOFY sales are on!) Ha!

Thanks heaps in advance and sorry for the waffling!