so maybe join a nature club or think about taking art classes. you could meet a lot of new people and have fun in the process!
also try taking good care of your appearance not to others tastes necessarily, but make yourself look good in a way you can admire.
Girls love guys who smell good, so a lvery light touch of cologne will work wonders, and also try and love and accept yourself. Doing so will give you much confidence.
Work out *enough to make your physical appearance appealing, but of course you don't have to go overboard with it
Eat the right foods and drink plenty of water, this will give you a feeling of vitality and make you healthier and therefore more attractive.
Doing all of these things will help you be more socially appealing, but of course conversation and body language are very important too, but the only way to learn those is observation and practice.