If you're aiming for the best ending in Kingdom Come: Deliverance 2, rescuing Sam is a crucial task. Here's how you can find and save him during the "Reckoning" quest.
As you approach the end of the main quest line, you'll discover that Sam is being held captive at Praguer's Camp, captured by Brabant. To save him, you'll need to infiltrate the camp, either through stealth or by force.
To move around the camp without raising suspicion, you'll need a guard's outfit. You can obtain this by either killing a guard and stealing his outfit, making sure to hide the body, or by looting one of the many chests scattered around the camp. Once you have the outfit equipped, you can freely explore the camp in search of Sam.
Screenshot by The Escapist
Sam is located in the barn on the left side of the camp, past the open area with a cooking fire. Use the ladder on the side of the barn to climb up and then drop down inside, where you'll confront Brabant. At this point, you have a choice: you can either kill or spare Brabant. Sparing him contributes to achieving the best ending, but the decision is yours.
After freeing Sam, it's not yet time to escape with him. He'll inform you about von Aulitz, who is also in the camp. It's advisable to deal with von Aulitz first, then find a horse, and finally return to Sam to get him out of the camp. Sam will be safe waiting for you, and this order makes the tasks easier since you'll need to carry him to the horse.
Von Aulitz is located in the main part of the camp. Wearing the guard outfit allows you to enter his room without being stopped by the guards outside. Upon finding von Aulitz, who is already dying, he'll ask for a dignified death. Granting this request is the most honorable choice. Alternatively, you can kill him brutally or leave him to die slowly. Interestingly, leaving him to die actually contributes to the best ending.
Once you've dealt with von Aulitz, your next steps are to retrieve Sam and find a horse. Sam will still be in the barn where you left him. If a guard questions you about moving him, simply say you're handling a body, which will dispel any suspicion. Head towards the camp gates, turn right, and follow the perimeter until you reach the stables.
Screenshot by The Escapist
At the stables, choose a horse and escape with Sam, bringing you one step closer to completing the main quests of Kingdom Come: Deliverance 2.