I was just thinking, can I play quite weak at the start and rely on my group, and slowly become more brave/ experienced? Just how Sam eventually fights Shelob!

You sure can, but are we talking some game limitations here? Because you are free to play how you want tbh, may be invest a bit more in your non-combat attributes, like Wisdom, Charisma and Intelligence. You'll have an opportunity to add some combat-related attributes like Strength and Dexterity later on, at level 4. But please consider raising your main class-related attribute (is marked with a star icon in character creation) to at least 14. Otherwise, the game may seem a bit too difficult for you.