i got73percentile in mains2020 will i get admission in amrita

Hello,
You have not mentioned your category and state.It will be helpful if you can give us such details as cut off is different for each category and Home state candidates and other state candidates.
However, you can calculate your expected rank using the formula given below
(100-your total percentile)*869010/100
869010 is the total number of candidates appeared in January session.
Your expected rank will be calculated as
(100-70)*869010/100=260703
So your expected rank will be around 260703.
2019 cut off data is not yet available with us but the cut off was as follows in 2018

• SC/ST category (open and state quota): 1-15000(opening rank), 15001-25000(closing rank)
• General category (open and state quota): 1-750(opening rank), 9501-10000(closing rank)
• State quota: 10001-12500(opening rank), 20001-22500 (Closing rank)

Considering this you may not get seat with your JEE main score.You have to appear for JEE main April session or appear AEEE.However, cut off is subjected to change it may increase or decrease slightly.