Gateway
Pohl is one of the last remaining giants from the golden age of science fiction.
Gateway is, in my opinion, one of his three best books. (The other two being the disturbing Mars exploration tale Man Plus and magnificent satire on advertising and consumer society The Space Merchants, which he co-wrote with Cyril Kornbluth).
In this future Earth is heavily overpopulated and resource starved and one Robinette Broadhead uses a lottery win to escape the brutal life of a shale miner to try his luck prospecting in an alien spacecraft from the alien adapted asteroid known as Gateway.
We see the present day in the form of sessions Broadhead has with a machine psychologist and in alternating chapters we’re told the story of what happened at Gateway.
It’s an interesting premise, well delivered. You really want to spend more time in the world Pohl created when you finish it.
I’d definitely recommend this for fans of science fiction. I would also say that you should probably avoid the sequels if you don’t want to be disappointed.