Astra theme search function

Hello I wanted to ad a search bar / a search icon on the header of my website which went good I got the icon there and u can search things in it. My Question/Problem now is that the result page of that search bar is in a completely different style then the rest of the website and I cant find a way to modify or edit that result page? That being the first problem the second which also is editing that result page is how or if I can edit the results someone gets when searching right now its just everything which the search word in it but I would want to change or at least modify it.

Thanks for reading and hopefully someone can answer me.

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