Stock Share Investment Loss Report missing in this year self assessment

Hi, I am new in the UK. I don't know should I must report my loss of shares investment in 2022 - 2023 year period. I got if no positive profit then no need to report into my self assessment on last year period. But if I have positive profit for my share investment. Could I claim back last year loss amount into this year self assessment? If yes, I only report some proof of the loss record last year ? If last year, I don't have report loss record but I need to claim that will be charge me any potential penalties ? Please advise me

Hi, 
 

You need to report them within 4 years of arising if you want to use them - : Capital Gains Manual  . Thank you.