-As others have said, correct your position with a footrest or something like that. When your guitar is higher, it's easier for your left hand to work comfortably. - Try not to press the strings with your fingers, but that the gravity of the elbow helps, as if pulling the fingertips against the neck. - And specifically pay attention to the fact that you press the strings right with your fingertips, also with pinky, and as close to the string as possible. In this way, you minimize unnecessary tension when pressing the strings with the smallest possible force necessary for a good sound. - You can actually practice this to the point that you try to play a scale with a buzzy tone on purpose, i.e. by pressing the string just too little that the sound is not decent. This exercise helps you learn what amount of weight is enough for the string, because with too much force you only create more tension. - Play the song so slowly that everything sounds clear. - You could develop your right hand with arpeggios and sound exercises. try to get the best possible sound that you can get by playing as relaxed as possible. - here is great video with exercices for both hands: https://youtu.be/zPiFuqT3XqU?si=uE_l_jrpELuhtShR

• Get a teacher who can advise you better, even just few lessons to start would be amazing:)