There are many options after taking physics, chemistry and biology is 12th standard.

Some of them are as follows:-

• You can go for BSc in subjects like microbiology, physics,  botany, zoology, chemistry. After BSc if you want to continue your studies then you can go for MSc then PHD. MSc can be done from IIT,  IISC by giving entrance exam like IIT JAM. You can also go for higher studies in abroad. 
• After BSc if you have interest in business then you can go for MBA by giving entrance exam like CAT for admission in IIM and various other institutes across India. 
• If you want to work in government sector then you can prepare and give exam conducted by UPSC for example like IAS,  IPS and so on. If you want to go in Indian Army then you can prepare for the same. These can be done after BSc or MSc.
• If you want to work in banking sector then you can give exams their respective exams. 
• If you want to go in teaching then it is also a good option. After BSc or MSc you can apply in schools or colleges or universities .
• If you take biotechnology in BSc then you can learn Bioinformatics side by side and then go into research work. As these are used in biomedical science and demand is increasing day by day. 

There are many options. But it totally depends upon you where your interest lies. 

If you still have any queries feel free to ask in the comment section down below.