edit wordpress customize website

Hi my website https://skurczybyki.eu

I am looking for a person to:
-edit some errors on the site
-sites 404 etc
-adding a blog to website increase traffic to the site
-adapting mailchimp
-visual improvement -changing colors, because there are different shades of black on each page
-adding a newsletter
-leads generation
-editing the contract tab
-scrolling animations - I want everything to be consistent