Well, depending on what you mean.
If you mean “where can I self publish both digitally and physically,” most major self publish platforms have print on demand arms for physical books. You can go to say Amazon, publish your book digitally, and decide to later on to add paperback or hardback with no problem.
However, if you mean “where can I publish my book digitally and then later get a publisher for the paperback/get it in physical stores,” you probably won’t. See, by publishing first online, you’ve sacrificed the first digital rights to the book. Small presses might not care and still could pick you up - some even specialize in finding authors and doing this. (Although ask yourself what they are actually giving you in exchange for publishing your book but that’s a whole different thing.)
Big presses and their imprints, however, especially the Big 5, aren’t going to be interested if it was published digitally first. There is the rare case where a book did so well digitally that a publishing house will buy the rights - Legends and Lattes and Dungeon Crawler Carl are recent examples - but those are the outliers who blew up, and most authors won’t do that.
Also, as an aside I always feel the need to mention: never pay someone to publish your book. A real publishing house will either pay you an advance or at least just take a cut of royalties. They’re hoping to make money from your books, not from your wallet. If anyone’s telling you they can publish your book but wants money from you up front, that’s a vanity press, and they’re great if you want to lose money and nothing else.