Teenage ages are 13-19, so I would give different advices as I grew in age but I don’t want to expose any sins, so I’ll write what I can.

13-15 At the moment you are lost, you don’t realise the things you are doing are not good for you. Slowly you will realise the importance of having Allaah in your life, the importance of prayer. Start praying now, don’t delay in praying to the One who Created you. Listen to your mum in what she says, she knows what is good for you. One day she will make a dua for you and your sister that will change your life for the better الحمدلله. Do not worry about people in school and what they think about you etc. These are only a few short years in your life then they will become past memories. It is better to be alone then to be with people who are a bad influence. It’s not weird to be alone at break time reading a book or something. But at the same time cherish the memories with your current best friend as you will lose contact with her after you finish school and you will try to look for her years after but have no trace of her. It can be anxious sometimes going to school but take a deep breath and remember Allaah is with you.

15-18 Do not judge others for how they are, you are not better then them and you were once the same. Try to sleep at good times, so you can have some energy for college. After college try not to procrastinate and try seeking islamic knowledge through madinah college etc and memorise some Qur’an. Try to learn some Arabic and stick with it. Attend classes if able if not it is okay to learn through online. Do not make your mum worry by wanting to attend classes far away. She is just worried about you and your sister and that is okay as the world can be a dangerous place sometimes. Give da’wah to your family using soft approaches. Cherish the moments with your family before you get married, you won’t see them everyday anymore. Give your mum head massages regularly and help her out when you can. Be grateful for eating mum’s food everyday. Be nice to your sister, you will appreciate her even more years later. Make more time for your dad, you will miss him too. Make time for your brother, you will regret not spending enough time with him. Spend time with your friends and cousins, you may not see them much later. Be grateful for your current stage in life, you won’t get it back!!

18-19 Think positive, make dua and Allaah will make things right at the right time. When you are married, please think before you speak. Some words spoken at the beginning can give bad memories although it was said in immaturity. When you are anxious speak to Allaah. Call your mum everyday and talk to your dad too when you can. Don’t forget to talk to your siblings too. It is going to be hard to adjust to a new lifestyle and things will be hard at times. You will have your highs and lows. Do not forget to read Qur’an everyday and try to memorise some as the Qur’an is shifaa and you don’t know yet how much you need it. Treat your in laws nicely. Attend classes, try make friends as that is harder once you have kids. Obey your husband in good. You have married young, so try not to worry too much just try your best in being a good wife. Maturity will come with age and life in shaa Allaah.