なくてはならないこと
something that is indispensable
やらなければならないこと
to urge (on one) the necessity of something―impress upon one the importance of something
It is necessary.
It's necessary.
to meet the need―fill a need―minister to one's needs
according to the need
to provide the necessities
所望のもの
something desired
to urge the necessity of―insist upon―something
A correction needs to be made.