Yes one can pursue more than one undergraduate degree in different subjects one after one. Complete bachelor degree in a subject then take admission for bachelor degree in a different subject.
Taking admission more than one time in bachelor is as simple as taking admission in bachelor degree first time after class 12. Anybody can if he/she wants to its not any problem.
Certainly it can be done legally if the said university allows it,
I am aware of a case where M.SC. examination in the same subject of anthropology was appeared by a candidate twice in subsequent sessons of the same University to inprove his grade from 32nd class to 1st class,
The said University had such provision for sitting for examinations multiple times to upgrade their classes,
Enquire from your University whether they permit further sitting for examination of a subject for which you have already sat and scored pass mark with some other university,
It will be illegal if you suppress the fact of your passing out the same examination from other university.
But during your first degree course period, if you are not able to complete the course there is always a provision to re-approach the university and clear all the pending papers . If you are going through the above mentioned situation.
Reference: UGC Act, 1956.
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