If you're familiar with the mechanics of Dungeons and Dragons then you will be happy to know that the ability to multi-class exists in Baldur's Gate 3. For those who may not be as familiar, this allows you to divide your points between two classes instead of sticking to the one you chose at the start of the game. This is primarily intended for experienced players who want to fully maximize their builds, while new players may want to shy away on their first playthrough, or at least use a guide to avoid ruining their build and needing to respec and start over. Multi-classing is easy to do, but not explained, so here's how you can expand your skillset between two classes in Baldur's Gate 3.
How to multi-class
You can choose to begin multi-classing anytime you level up in Baldur's Gate 3 after starting the game and earning your first level. You can only do this when you have a level-up available, so make sure to remember to do so when you have the opportunity.
Step 1: Finish the opening and level up by any means.
Step 2: Click on the upward arrow on your character portrait to go to the level-up screen.
Step 3: Select the button at the top right of the level up box with the image of two crossed weapons and a plus above it. When you mouse over it it will say Add Class.
Step 4: You will now be able to choose any of the classes you haven't chosen yet to multi-class in.
If you choose to multi-class, you will only level up one class at a time, preventing you from diving as deep into a single class. Keep that in mind when choosing to split your focus.