Roderika is a very important NPC in Elden Ring, as she is the one who improves your helper spirits, but you need to progress in her quests for you to be able to do that.
Elden Ring – How to complete Roderika’s quests
First find Roderika in Stormvill, just follow the path to Margit and she will be close to a lost grace on the way to Stormvill, talk to her until you run out of dialogues and continue the game normally. After some time exploring the castle it was time to go to the round table.
Go to the round table to find Roderika by the fireplace. She will reward you for your help with a golden seed. After finishing the conversation, talk to the blacksmith. Open the dialog menu and choose “About Roderika”. Hewg will share his thoughts on the new roundtable guest. Talk to Roderika you talked to the blacksmith and repeat the dialogue with them two more times to recharge the area.
After that, Roderika will have the power to improve your spirits, becoming one of the most useful NPCs in the game, as these spirits are essential for you to do well in battle.