How to sell / buy house / sort mortgage

[houseselling]

Can anyone tell me the order that things happen in?

Do we get our house valued, speak to the bank and sell then find a house to buy?

classic order:

ask bank about mortgage options.
agree with partner if you want to increase, decrease mortgage so you know how much you’re borrowing
get valuation by agents on your property and check out local recent sales on right move etc
start house hunting within your budget
offer on another house and
put yours on market (order of this is up to you. A seller may expect you to have an offer first)
lawyers and agents do the rest
bank approve finances once you have an offer on another home

you can just sell or buy if you’re in the position to. Depends on your finances, so check with your bank first.

I'd get the EA valuation(s) first so you have an idea of the amount of money you'll have for the deposit on your next house. Then look at online mortgage calculators to see how much you can borrow/what monthly payment you're happy with, and you could get a Mortgage in Principle.
You can house hunt, but I think most sellers will want you to be under offer before accepting your offer, so probably put yours on the market first.