lock Excel cell after value is entered!!

I have two worksheets. on sheet1 i have data which is.

ID	Name	Last Due	Mthy Rent	Total	Paid
101	Sophia	0	300	300
102	Liam	-50	250	200
103	Jacob	0	300	300

On sheet2 i have made search box using Index feature which is like

ID
Last Bal
Monthly
Total
Paid

I have managed to get the data when i entered ID in Cell B2 and when i am entering data in B5. it should automatically enter into sheet1 paid column respective to their ID. after that it should be copy and paste special as value and locked that cell. so that i cant enter any value in it.
for reference i am uploading excel file here.