I really understand - I brought up my lovely DS on my own (he's 21 now) from when he was just two, and I had some of these fears and worries too.
I am really happy to confirm that it was FINE! When they're babies, it's all just the same, and as they get older you just learn 'stuff' along with them 😀.
DS had some (very short) periods where he asked about his dad, and I told him all of the good features that his dad had - didn't mention the bad bits! Also pointed out that families come in all shapes and sizes, and he was happy with that!
Got him into air cadets at 13, so he had some really good male re models (along with other family members).
We learnt together how to tie a tie and how to shave from the Internet 🤣.
I was worried that he'd be like his dad, but as I brought him up, he is MUCH more like me, and is brilliant, kind, thoughtful and all my own work! I would go back and do it all again in a heartbeat.
Congratulations - you are about to start on a wonderful adventure, and it will all be just fine 😀.