Why is my Dawn theme checkout not working and site speed reduced?

[DecorAspect]

Hello, after i unistalled a few apps, my site checkout doesn't work and also the speed is reduced. Can someone help me?

[DecorAspect]

I think I've made a mess...

site: decoraspect.com

I need to remake the site from scratch

[DecorAspect]

@Drekliyer Problems resolved but my site speed is still low. What can I do to increase it?