Oil painting itself dates back to early times in Europe. It was discovered inside caves where men mixed together soot, soil and animal fats to produce the earliest oil paints. These were therefore used to create their imagery on the actual cave walls.
Later it was discovered that, if oils were taken from nuts and linseed and were mixed with pigment, it would make bright oily colours. The beauty of oils is the fact that, if you do make errors on your canvas, you can get the colour off if you dip a piece of rag in turpentine and just wipe it off.
So, what do you really need? First of all, I would advise you to wear a big apron, or some kind of overall, before you start to paint. A palette knife along with a palette. The knife you will find very handy to move oil on to your canvas, but you can also move the paint around with this.
Now, if you can manage to pay for an easel this will be an advantage and there are a number of types to select from. Old jam jars can be used for washing out your brushes or solvents. Old pieces of rag, or dippers as well, are somewhat a good idea as they can be clipped on to the edge of your palette to contain solvent as well as painting mediums.
Solvents, such as distilled turpentine and white spirit, for thinning oil colours and also for cleaning your equipment and brushes, can be used to great effect. Charcoal too is handy for outlining the subject that you wish to paint. As for your basic palette, colours I have listed here are a general sort of palette which, of course, you can always add to.
Cadium lemon, yellow and red, raw umber, titanium white, yellow ochre, burnt sienna, viridian hue, french ultramarine, pthalo blue, permanent alizarin crimson, and permanent rose.
Then, besides paper or a canvas, you can put oil paint on glass, hardboard, walls, wooden furniture and plaster if you prepare it first and use a primer.
Going to brushes, fine hog brushes are probably the best choice as they retain their shape and are pretty good for fine detailing in your work. As for brush types, a large or medium sized flat brush works well. A medium no. 6, or a large no. 10 or 12.
These are good when you want to paint on large areas of colour. If you then want to do thinner, narrow lines you can use the tip of your brush. Very good too for blending your colour around your canvas.
Now for scumbling or dabbing on small patches of colour. You may possibly use a medium sized round no. 6 brush, which would work well too for putting on broad areas of colour. For extremely fine details, and even highlighting, you could experiment with a no. 2 small sized round brush.
If you would like to sketch outside, canvas boards are good, quite strong, and, I would say, are more manageable as they take up less space. Stretched canvases are in all probability the most used, but you can even construct these yourself.
The other choice of surface left to you is oil colour paper which has a textured surface, but can be used for oils or acrylics.