How do I stop Safari on my iPad from reloading tabs once they are already open? For instance, I like reading Quora. They regularly send me digests to my email. What I do is I click the link from the email that opens the digest in Safari tab. I usually prefer to leave those open tabs until later on (usually Sunday) when I go through many tabs at once and read through them all.

Well, this works really well on Chrome browser on my Windows desktop but on my iPad, when I open Safari (say after a week or so) it reloads the page instead of showing what was opened there originally (a week ago.) This results in the old digest being completely reloaded with some new stuff.

Is there any way to make Safari on my iPad stop reloading pages and just keep what was shown there originally? It is very annoying!
Probably not.  You need to think of the nature of the iPad.

It is RAM constrained (and battery constrained, but that probably doesn't affect this as much as RAM), so it often suspends apps so they can be "reconstituted".

Depending on what you do in the week (a long time in app land) the pages would be suspended and removed from memory.  Reopen the browser (and this would be any browser on the iPad, not just Safari) it has to get the pages again to show.

So.. this is what iPads (and to some extent android devices) do.  It remembers where you were and re-gets the page.  Now you could do a Reading List, or even use Pocket (I think Pocket takes a snapshot in time, so may work better).  Those may bring you closer to where you want to be.  But the tabs will be reloaded, because they were gone way before you re-opened safari