So because its not easy to understand what you have to do ill try explaining how the game works as best i can
 
The goal is to find the girls and sneak up on them which means building up the blue bar (keep the left mouse button pressed) before the red one fills (which lets the girl escape)
You can build up your energy with skills (right click on icons) which lets you either move faster or let the girl ignore you when she looks at you, if she looks at you for too long she gets energy which lets her run away faster
 
Skills have two types of attributes the type of the skill (color) and the category (icon)
Blue skills build up energy for you while a condition is true, pink skills are traps that build a lot of energy if something happens while the skill is active (you need to learn the tells and use the skill before the girl does the thing), orange skills change what the girl is doing and green is everything else
Some skills can interrupt when a girl does something (like the pink heart when she tries to look over her shoulder) which ofcourse also helps not having her look at you
 
Most girls react to some type of skill category so for example one girl gets energy if you use heart skills but another girl gets energy unless you heart skills so you have to learn who does what, autotranslator helps with that
 
You can arrange your skills after the tutorial and every skill makes you better if you use it enough, this also unlocks new skills for you so try using every skill you have
The menu shows you what skill unlocks what if you hover, dont even need autotranslator for that
 
The map eventually shows you where girls can show up but not when
If its anything like marunomi or procreation of chimera you probably have to catch the girls in a certain order to get to the main endings so if you get good at catching girls but not get new content maybe try not catching certain girls or something