How to relate opportunity to contact upon creation

Is it possible to add a contact field to opportunities. Thereby making also it possible to combine the opportunity directly to a contact, when creating it.

I have sort of been able to create this, but it creates a new panel under the chosen contact, and does not the show with the other opportunities combined with the chosen contact. I would like it to be combined with the other opportunities.

Basically, I’m looking for a feature add the chosen contact to the other contacts under the chosen opportunity.