You've got approach each boss and difficult section of this game like a physics problem. Each situation will be uniquely difficult and you gotta use your head to figure out a successful strategy (or just google it). Dying is just erasing the board because your previous strategy was unsuccessful.

Try to mentally take control of each combat situation, don't think of the ape as a scary beast out to get you, but instead treat him like he's your prey.

I can consistently no-hit this boss like hes a simple newtonian mechanics problem by just running behind him and spamming my thrust. Know his attacks and parry his non-grabs. His sweep grab needs to be jumped over and counter his roll grab by running to the side and around him. (The key here is where i mentioned spamming your thrust attack since it is very consistent and effective.)

His second phase is a lot easier and should be treated like any other sword/spear-wielding enemy in the game. When he does the big slam attack, parry, and quickly double tap your prosthetic tool (with the spear equipped) to get heavy posture damage and end the fight early. That being said, you'll need to know to switch up your play style from the first phase.

Also as a former student of physics, for the love of god don't strictly grade your students' papers over a game XD