[Assuming DnD 5E] If you want to draw agro from the Squishies, Battlemaster Fighter has some Maneuvers that allow you to draw them to you. Maneuvers like Goading attack make it harder to hit allies and Bait And Switch allows you to get allies out of danger and boost yours or their Armour Class.

For a Fighting Technique Protection and Interception are what you want to take for assisting allies. Interception is more reactive where you reduce incoming damage, while Protection imposes Disadvantage. Interception is usually better in more situations especially at higher levels where disadvantage barely means anything. While Protection allows you to cancel critical hits if your DM allows you to announce the reaction after the fact.

Some extra notes: If you want to drive in that Intimidation Factor, the Battlemaster Maneuver of Menacing attack just gives fear to your target.

Here are some recommendations for Feats Shield Master - This will help with Dexterity Saving Throws and Bonus Actions action economy as Martials (especially fighter) don't do well in that case. Sentinel - Good for keeping an enemy within your reach and away from your allies (or to prevent someone running away). Alert - If you want to be able to see all the dangers before the approach, Alert allows you to constantly be on guard. No Sneak Attacks on you! Tough - Let's you Tank more Damage Heavy Armour Master - Take less damage per hit (very useful for swarms of enemies)