Let's talk about the Spare again.
I hope he doesn't mind, though you never know who may be reading this.
Prince Harry brings up the real issue of inheritance, in Britain or UK known as primogeniture. It basically means first in, first served, and being second is always the runner up. You'll only win if you bump the first one off, or the first one abdicates.
And it only applies, or used to apply, for many centuries, to males. You will eventually be outclassed and branched out or broken off the lineage, when the first starts sprouting sprogs. (look that one up).
This is why Princess Catherine is important and trumps Duchess Meghan. Prince William, can choose if he wants, to make Catherine his Queen, but that will never happen to Duchess Meghan. The only way it would happen is fratricide, but, if that happens it would be truly evil even if they covered it up and pretended someone else did it. This is why all the conspiracies surround Princess Diana's death.
i'm still getting used to the ever changing titles and names its so confusing because the abdicating uncle was known to everyone as King Edward, (for a brief period) but insiders called him David, and King George was actually called Bertie (or Albert).
Anyway back to Prince Harry. Like Bertie he is the spare. So even if William may choose to give up his inheritance for a mess of pottage (though not likely, plus he's already married) Harry will receive nothing, as he's already exiled himself. And it (the crown) will go to little Prince George. Unless there is a reconciliation or understanding between brothers, Harry will not be HRH. He won't ever be His Majesty.
This doesn't just happen in Royal families. All of aristocracy in the UK adhere to this rule, of primogeniture as they need firstborn sons to inherit their vast estates. What happens to the second sons? Well back in Victorian times because they had no inheritance it was common to send them away to the colonies. They were called Remittance men.
The stories of Remittance men are mostly very sad. Some made the most of it, but often they fell into trouble, were given little but a yearly allowance, and were absolutely useless to anyone. They couldn't work for a living and most likely didn't have the skills to do so. Many turned to crime, if they were not already rogues, vagabonds, pirates, drunks and thieves.