Yes, Ratnesh,

You may take admission in BSc if you have passed 12th with atleast 50% and had maths as a compulsory subject in 11th and 12th.

You can apply in colleges near you and if you are working then there are many night schools and long distance study institutes also, like IGNOU.

I hope you achieve your dreams.

For more information on BSc click here :  B.Sc

Hello dear aspirant

There are many universities that doesn't impose any age barrier for graduation courses.
Even the top universities,  such as university of Delhi and Mumbai university allow candidates to apply for graduation many years after they passed class 12th.
So,  you can definitely apply for graduation in this session or the next session.
Hope I am clear

Hello aspirant, hope you are doing good in life. 

Yes absolutely you can apply for the form in 2020. There is no age restriction criteria, the only eligibility is the aggregate which is normally 60% in all the reputed colleges. 

If you have that much aggregate you can definitely take admission. All the best, feel free to comment 

Hello Aspirant
As you say that you passed 12th in 2016. You can BSC in 2020. There are many University in which age limit is not there .
Thanks