Can you make a cryptocurrency like Ripple or Stellar?

[legoman02]

A friend of mine wants to create a cryptocurrency for his business.
It has to be centralized (like bank), and very fast like ripple or stellar.

He will 100% fund this project from the very beginning.
The only problem is that I am not familiar with blockchain technology at all.

Could anyone tell me if it's possible, how long it takes with how many people, etc.

I did a little research and apparently ripple does not require mining but all nodes
are controlled by ripple itself? Would it cost a lot to set up such nodes and  still maintain that kind of speed?

What do I need to know about POC protocol? Are we allowed to use it?

I would really appreciate any help. And please let me know if anyone is interested in participating
in this project, even remotely if you want to. We don't live in english-speaking country by the way.
Everything will be funded.

[Anonymous Kid]

Of course its possible but its by no means easy. If anyone could do it, everyone would be rich af.

You'll need an experienced dev in blockchain/decentralised systems (this is very difficult and complicated).
If you look online you should be able to find source codes on these projects and just fork the github repos.
It depends on how specialised you want it to be.

Can I ask why he needs a seperate cryptocurrency?
What is wrong with using an already existing and built ecosystem?

[legoman02]

He wants nothing special added to the coin.
Is it still really hard?

he wants to make a new cryptocurrency because He wants the price to remain still.
like tether, but with fast speed like ripple.

What should I read in order to make coin like ripple?
Thank you for your reply btw.