Hi aiming, your worries are exactly the same as mine were a few months ago.
I went back to work when my daughter was 8 months. After a difficult start to breastfeeding, it had settled down to being easy and enjoyable and a special part of every day for us. I was dreading having to be away from her during the day.
I expressed in my breaks at work. It wasn't tonnes of fun, just a bit boring. But I would look at pics of dd on my phone, or read a magazine and it actually became a bit of a nice peaceful break from my work.
Dd settled in brilliantly with her childminder. She'd cry at drop-off at first but she loves being with the other children. She didn't drink very much in the day, it soon settled down to about 70-90ml, which was fairly quick for me to express. I'd feed her when I picked her up and it was a lovely way to say hello and reconnect.
She's now 14 months and still happily breastfeeding. I don't bother expressing in the day anymore. My supply is settled and dd drinks some cows milk in the day.
It really can work out well. You clearly have the motivation to make it work. It wasn't nearly as difficult/complicated as I thought, and I'm sure it'll be the same for you