What both these guys have said, but I'll make a suggestion to pick up IQ first on offense. Some might disagree with this pick.
IQ is considered a "weak" pick for the meta right now (because her unique gadget doesn't have as big an impact on the game as other offensive operators) but the advantage of picking her early is her gadget is an excellent learning tool for new players.
Your gadget isn't mission critical, which alleviates pressure on you, but you can use it to learn how to recognize cameras, traps, etc early on.
She also has a very well-rounded loadout option so you can try a variety of weapon types.