yes you can for instant result but not for long time result.

Yes you can. I do Income Tax for locals. I use Facebook to promote my business to locals.

I find the requests coming thourug my website better and more volume than facebook or other socail media. Ok, in my domain probably matters this too.

Use paid tool for getting lots of traffic towards the website.

yeah you can use all social networks and promote your brand easily social media is the most power full place for marketing Facebook and Instagram have huge audience