Please explain this sir

Update bit is not clear to me completely .

hello @piyushkumar999999
update bit function is responsible for updating a particular bit of a number.
what we are doing is we first clearing exisiting bit and then taking or with new bit value.

for example->

1101 let say i want to update this 1 to 0.
for that first i will clear it i.e i will set it to 0
1001 .
after that i will take or with 0<<2
1001 final result.
now watch the video again it will make sense