On Youtube I get asked quite often, what knife do I recommend?
This is a very tricky question because, yes I am familiar with knives, yes I teach knife combat, but I don't know anything about you.
Generally speaking a medium to small sized utility folder is a good option for EDC/SD (Self-defense) when you include general legality.
One of the best knives that fits this criteria is the Spyderco Delica.
There are more affordable knives that are similar such as the Schrade Team Primos knife that I got from Primalpunch. It had a $40 price tag but you can get it online for $20.
Another good starting knife in the $20 range is the Smith & Wesson Urban Camo Karambit if you are into martial arts.
Once you become more experienced and learn better knife care and knife combat skills, then I suggest you get better quality knives that will cost more. It's also good to have experiences with a variety of different types of knives so that you have a wide range of knowledge and experience. Fixed blades, neck knives, tactical knives, survival knives, hunting knives, diving knives, throwing knives, double edged knives, butterfly knives, slip joint folders, and even multi-tools.
I can tell you which knives that I like the most out of the ones that I own.
My top 4
SNAGette by Krudo Knives
SNAG live blade folder by Krudo Knives
BG911 by Knives STI
P001 Bodyguard by Knives STI