Forms for Online Self-Assessment

Hello, I have been using a commercial software provider's service to file my self-assessment returns, but would like to do it by myself next time. I have 2 questions and would be grateful for your help: 1) As far as I know, some forms are only available in hard copy and so we must use a commercial software if we want to file our self-assessment online. May I know whether SA106 and SA109 can be filled out via HMRC's website without the use of commercial software? 2) If I've been using a commercial software to send my self-assessment and now do it via HMRC's website, do I have to inform HMRC first? Thank you in advance for your advice and help. Best wishes.

Hi,
Please find guidance at the following:
SA106
Foreign (2024)
SA-109
Residence, remittance basis etc notes
There is also information re SA-109 on the following Community Forum
Form SA109
Please also find Technical Support at:
Technical support with HMRC online services.
Thank you.