Newbie bike recommendation

Hi I just learnt to ride on my friends Unicorn and just know the basics. Not confident enough to take out to the city traffic but can handle it around less crowded roads .Gear shifting not that intuitive yet as of now , needs practice, (Drives car well).Also hesitant to ask for others bikes.

Should I buy a second hand commuter first or a decent new one like a CB350RS ? Will I beaking a mistake if I take a new one right from the beginning ? What factors would you consider that would incline me to take a second hand one ?

I would like to go on long drives occasionally and use it in the city as well.