could you explain a bit better please .

do you want to do a border of wild flowers or scatter wild flower seeds on the lawn?

My local council made some wild flower sections on a couple of roadside verges last year and they looked fabulous for weeks - so much so that I phoned them to say how much we liked them.
They seemed to have cleared the ground first and started with a fine tilth. They used a seed mix from Leeds University? which contained some non british flowers to get a long flowering period. I've noticed that they cleared the 'bed' in the spring and have resown it for a new display of wildflowers this year.
From my own research it seems that this is the best way to get a good range of flowers. Expecting wildflowers to grow amongst the grass of your lawn will only lead to disappointment as the grass eventually overwhelms the flowers. To get the best display needs annual work.