Hi, You have a few options re paint - you can sand off any varnish with sandpaper - rough then progressively finer sandpaper to get a clean wood surface to paint. If there is any paint on the furniture already, you could use paint stripper or an electric sander to get a clean surface to paint on. Then wipe down to remove any dust and paint with either normal wood paint or, what I find to be a much better option, Fusion Mineral Paint - I have bought from this website before: https://www.clairescrafthouse.co.uk/fus ... gJWKPD_BwE
and they have beautiful colours and finish, no odour and two coats gives great coverage. Then you just oil with hemp oil once dry. Annie Sloan chalk paint is similar. Depending on what effect you are looking for, it might be worth you getting in contact with Lynda Robinson of Touchwood Vintage Designs as well - she offers very reasonably priced courses for decorating furniture, or can come and help you do it in situ and teach technique so you can do it yourself or will take the furniture away and do it for you - she also does the most beautiful decoupage with designer wallpapers as well - this is her insta https://www.instagram.com/touchwood_vin ... gns/?hl=en
Hope that helps. The pic is a chest of drawers that I did myself with help from Lynda with Christian Lacroix paper and Fusion paint - from boring to fabulous!