ᐅ Opening for water connection and bathtub faucet installation

Hello forum,
I have moved into an old house and want to install a bathtub.

On the other side, there is a washbasin.
I need to modify the water pipe so that I can connect a bathtub faucet on one side and a washbasin on the other.

Also, I need to somehow close the hole again. I really need your advice on how to do all of this in a way that I can understand.

Thank you very much, Olli

For some reason, the image did not upload correctly.

I would probably replace the angle valve with one that has two outlets and then connect the bathtub faucet using a flexible hose.