I bought Schwalbe Doc Blue 500ml. It comes with a smaller 60ml bottle.
On my road bike I put 30 ml in each tyre.
I refill every three months or so. Although if I have a puncture that's sealed - I had one which sprayed sealant before it sealed - I top up.
I run at 75/80psi. I did 60km on the Waterford Greenway at about 60psi, using a handpump after the puncture described above sealed. I had no problems at 60psi. Rolled fine.
I changed tyres using my normal tyre levers though there are tubeless specific ones for sale.
I used a Giant Control Tank along with my track pump to seat a tyre. I found the pump wasn't sufficient.
Yes to your last question.