OK for the Xeelee series (by Stephen Baxter), you’re really spoiled for choice… the author designed all the books to be standalone, doesn’t really do ‘cliffhangers’. But he has a suggested reading order:

Vacuum Diagrams (collection of short stories which will set out the overal story of the universe)

Timelike Infinity / Ring (tells the story of a character integral to the series, Michael Poole)

Raft and Flux (incidents amongst the wider background)

Destiny’s Children (three-parter in the same universe, exploring different evolutions of humanity)

Then whatever else you like the sound of.

As an example of the sorts of timescales he writes over, ‘Xeelee: Redemption’ is set between the years 4060 and 5,000,000,000! Personally I prefer long books over short stories, which to me always feel like they end just as they get going. So while Vacuum Diagrams is excellent, if the same is true for you, maybe jump in with Timelike Infinity. It’s a shame all my stuff is in storage atm as I could post you some of these. Hopefully you can find them at your local library.

For Banks, there’s an excellent reading order here: https://www.howtoread.me/the-culture-reading-order/