You can start work without a National Insurance number if you can prove you have the right to work in the UK.
You do not need a National Insurance number to apply to the EU Settlement Scheme.
If you do not already have a National Insurance number, you only need to apply for one if you’re planning to;
Obtain UK National Insurance number in the UK if you are planning to work,claim benefits,pay class 3 for voluntary National insurance contributions
pay class 3 for voluntary National insurance contributions
Before you Apply
Check how to find a lost National insurance number
if you are a residence ages 19 or under
you will normally be sent a national insurance number automatically 3 months before your 16th birthay,if both the following are true;
-You live in the UK
-A parent has filled in a child benefit claim form for you
-if you are aged 16 to 19 and did not get one ,call HM Revenue and Customs
Obtain UK National Insurance number in the UK
if you are moving to UK
If you have a biometric residence permit (BRP), you might have a National Insurance number already – it will be printed on the back of your BRP if you do.
If you do not have a National Insurance number, you must apply for one if you plan to work, apply for a student loan or claim benefits. You can only apply once you’re in the UK.
If you are applying for benefits or a student loan
You can apply for a National Insurance Number as part of your application for benefits or a student loan