level 3 and university

hi everyone, i’ve just finished level 2 business and i’m starting level 3 national diploma at college, can i go to university after that and what can i do?

Can you be more specific about the "level 3 national diploma" you're doing? If you're talking about a Pearson BTEC Level 3 National Diploma, then that's the equivalent of two A levels. It will be quite difficult (although not impossible) to gain entry to university with just that qualification.
For reference, a Pearson BTEC Level 3 National Extended Diploma is the equivalent of three A levels, which would be more normal. Similarly, a Pearson BTEC Level 3 National Extended Certificate is the equivalent of one A level.

it’s Pearson Btec Level 3 National Diploma in Business and Level 2 i did for Business was Extended Certificate