To put it simply, if your golf swing is off then your golf game will also be off.
You need to get your swing right in order to produce better golf shots.
If you're slicing the ball you will lose distance and you will also be less accurate.
Both of these factors will drive your golf score higher and make the game frustrating.
There are many factors at play throughout the golf swing but what you need to address initially is your grip.
If you grip is wrong it will make your muscles tense which will prevent you from having a smooth swing.
On top of that when the grip is tight your hands will come too much into the swing which can make you pull or push the ball on execution.
All of the above is detrimental to a good golf game.
So to improve this you need to understand the mechanics and to do this you need to start with the fundamentals, beginning with your address and posture.
Then start checking your grip.
Next you will address your tempo and instead of the small muscles doing the work you want to get the bigger muscles into the swing.
Start by taking the club straight back with the face of the club square to the ball.
Initially you may need to shorten the swing so as to get the mechanics right and as you become more confident your swing will then naturally start to extend.
Essentially to explain mechanics, think of it this way, the mechanics are the very movements that are engaged throughout the swing.
Your goal is to identify your mechanics in your swing, then you need to study the correct mechanics and build on a sound foundation that gets the right movements engaged.
If you do all of the above then your golf swing will produce shots that are accurate and shots that produce distance.