Depending on your current skills you have a couple of options: build what you want using a CMS system like Wordpress where you can add on modules/plugins to build in the functionality that you want, or search for a third party who has already integrated these things and will offer it to you as a Service.
If you go the CMS+plugins/module way there are usually costs associated with some of the plugins required to make your life easier (not expensive but an easy way to ensure you have some access to support if needed, there are almost always free alternatives).
If you go for the integrated service option I would ask around for some solid advice on selecting a good service as there is HUGE variation in the quality of what is on offer. There are a gazzillion companies all wanting to build you a website with their software, you don't want to have anything to do with 99% of them. I've not looked at them recently enough to warrant giving any advice or recommendations past that.