Hi @dafreak
To remove the base cover you need to move it in a clockwise direction and then lift after you have removed all 10 screws.
Here's the [https://download.lenovo.com/consumer/mobiles_pub/v14_and_v15_hmm_201911.pdf|hardware maintenance manual] for the laptop.
Go to p.42 to view the procedure to remove the base cover.
Take note that there are two different size screws used i.e. M2.5 × 7 mm (6) and M2.5 × 4 mm (4). So make sure that they go back into their respective screw holes when replacing the cover.