The physical skills of punching, kicking, throwing, locking etc., are usually referred to as “self defence”.
They are also know as the “hard skills”.
To have a complete system to protect yourself from violence, you need to learn strategies to de-escalate a situation and/or dissuade a would be attacker from actually physically assaulting you. This is usually by using assertive body language and voice. This is sometimes referred to the “soft skills”. If you get this part right, you end up not having to fight at all, which has to be the best result.
“Self Protection” is taken to mean a combination of both hard skills and the soft skills. The soft skills done right, can help diffuse the situation making real violence unnecessary. But if the aggressor persists and escalates the situation to the point where you believe violence is imminent, then the soft skills can be used to line the aggressor up for a preemptive strike to a vulnerable (vital) point so that you can strike them before they even realise what you are doing.
Legally, you are allowed to strike first if you honestly and sincerely believe that you are in imminent danger of being attacked (though you might be called upon to justify this, along with the level of violence used in your response). If the soft skills are done correctly, then any witnesses or CCTV footage will show from your body language that you did not actually want to fight. So the soft skills done right can also help you with any legal ramifications.
Note: Self protection if legal, fighting is not! A fight is seen as consensual by all parties involved (regardless of provocation). Self protection is when one (or more) party takes the choice away from the other one and forces violence upon them. Then you can strike first as self protection.
So simply learning to fight is therefore not the most efficient method of defending yourself (practically or legally) as it excludes a number of important skills and strategies.