National insurance class 3 contributions questions

[Tennislover]

Hello all,
I have been a DIY professional for 17 years but in 2019 deactivated self employment with the help of my accountant.
I unfortunately lost a family member at the time which really put me off my stroke.
I had a few years on universal credit thereafter but left in 2023 as I didn't like the idea of being on the dole.
I haven't returned to my work yet and at some point wish to do so but thankfully I have received help from some other family members to carry me through this period.
I would like to pay three years of NI contributions from 2023 to 2026.
How do I go about this?
Do I pay online through the personal tax account or do I call the HMRC phone number?
Also I haven't worked in three years and haven't been on Universal Credit so will they ask me about this or just take my payment?
Any help with this would be much appreciated.