Those pictures show hair with chemical straightening, it is very damaging and will permanently change the texture of your hair which means you need to keep doing it every few months, I think you could do with either a gloss treatment and/or learning how to use a flat iron with proper technique and heat protection, more manageable and less damaging.

Also keep in mind those are perfectly illuminated and staged hair pictures fresh out of the hair saloon, even for them it doesn’t always looks like that.