EPF Payment By Self In A Start Up

Dear Experts,
I have recently joined a start up which employs less than 10 people and hence is not registered with EPFO. Before this I have been working with big companies which deduct EPF.
I have 2 questions:
1. How do I pay to invest into my EPFO account? I have a EPFO UAN.
2. I have an inactive EPF account with an old employer (inoperative since 10 years, managed by the company's trust). Since my current employer is not registered with EPFO, can I transfer the old inoperative account to my UAN linked account?
Thank you for your guidance.

if the company is not registered with AEPF then you can't contribute. it will be as inoperative mode only or you can withdraw

I think the ability to transfer all old balances from various accounts to your UAN is also only for live accounts. If the account is dormant and there is no employer to file the Form 13, then you can not transfer the balances to that account. Unfortunately you should have done that when you were still working in the previous company.