Specialist firms will strip the top and lay new turf.
Or you could hire a mechanical cultivator and prepare a tilth and hand sow seed, although it’s probably best to do early or late in the season. Use weed killer and or dig up the weeds.
I used John Innes as a top soil/feed and rolled with a garden roller, then literally watered it day and night until the shoots appear. They seed packet said it won’t work if nothing appears after a week, mine took almost three and survived several frosts.
Also used the seed at five times the recommended coverage.
Do you think it was turf previously? (It’s hard to recognise things in your photo; are those weeds or maybe daffodils I can see?) There may be plants there that will come up later, e.g. bulbs. If you have other things to get on with then it may be best to wait.
On the other hand if you’re sure it was previously just grass then I’m sure you can find videos etc. describing how to seed or turf it. A good job takes a lot of effort.
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