help! ( how to reduce SPH/myopia/prevent it from increasing)

Hi currently 18 year old this year, just went to the eye doctor today and got it checked. 1 year ago i was -4 on my right eye and now im -5 on my right eye. My asian mum is mad that my myopia has increased and said that it was because i was playing games for too long , straining my eye etc.
Any ways to help decrease my SPH?/prevent it from increasing alot every year? Thank you 🙏