Audit and optimise every area of my wordpress site

I need an audit and relevant fixes made on my website. Just need someone to give it a 'once over' and test everything to ee what's working and isn't, identify anything that needs adding or improving, make the changes, clean up the back end so there's nothing clogging things up and remove any unncessary.

Needs to cover:
- Analytics audit with recommendations. I have GA installed but not sure it's working
- Security Audit to make sure I have all necessary measures in place
- Make sure my site is GDPR compliant. I have the privacy policy done and emails sent out - need to make sure rest of site (forms, cookies etc are compliant)
- Speed audit and relevant fixes
- SEO Audit
- Branding audit
- UI/UX Audit
- Automation Audit
- Social media audit

I have attached a full list I've been given which I'm told should be checked out which I've attached which should make it easier, but you may have your own list.

A few things that aren't working:

- contact forms not working (I don't receive emails)
- my payment icons at the bottom of the page have gone missing
- Can't change admin email - do not receive confirmation email to new address