How can I earn money online? I am a student of BS biochemistry. I am girl so I can’t do any job physically outside in my free time.

If I know correctly you can’t freelancer Bio Chemistry work from online since it’s not a digital service. You have to be on the lab or something and working physically. If you want to work from home you should learn some skill that you can offer from home through internet.

You can start freelancing on various platform after learning skills like Logo Design, Web Development, App Development, Android Game Development, Animation, Photography or anything that is possible to provide digitally.