If a Muslim girl and Muslim boy hugs and kisses before marriage will it be considered as zina?

So I know a guy who has committed these things and now he's asking me will he has to marry that girl in the future cause he has seen in Sur'ah an nur that **if fornication takes place the girl has to marry a mushrik and the boy would have to marry a mushrika**. Now he's question is ...**will this be Zina?** And **can they marry anyone they wants to?** Or **they will have to marry themselves only**?