Yes, that is normal. Okay.. That is again, something else.
Okay, quick dual wielding: Anyone can do it, but it is severely limited at first:
1. It costs a bonus action. [per RAW, one must make a main hand attack first, butin BG3 this is not the case]
2. You can only use light weapons.
3. Ability modifiers aren't added
You can augment it:
1. Two weapon fighting style [Fighter, Ranger] - Adds the ability score modifier
2. Dual Wielding Feat [anyone] - +1 AC for second weapon, and can wield non-light [1H] weapons.
[ In BG3, if you *have* a bonus action and just attack, it does it in one go, so yes, you attack with both weapons in one go, but you'll spend both an aciton and bonus action. ]