UK Tax return

[asu1z]

I will be very thankful if someone could explain, What is tax return document called in UK?

I am self employed and I need a tax return to send in support of HSMP case.

I am aware that employed people get P60 which is a tax return but for self employed, how can we get a tax return?

I will be very thankful to you if someone could provide me the sample of it.