Am I supposed to sort out the mortgage first then start looking for the property or the other way around?

I'm looking for a mortgage (UK). I don't know if I should first sort out the mortgage or should I firstly find the property?Am I supposed to sort out the mortgage first then start looking for the property or the other way around?
Not sure about it in the UK but I got preapproved 1st and worked some numbers to know what I would be comfortable paying for a house in the US inclusive of taxes and insurance. What you can get approved for is often MORE than you want/need to spend to be comfortable (in Texas anyway) After that I began to look in thta price range. In my opinion, it saved me alot of time looking at things that would not fit my budget.Am I supposed to sort out the mortgage first then start looking for the property or the other way around?
Go to a lender to see what you are qualified for, then look for a property.
First you get preapproved which is fast and easy then search for houses

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