Do olianders like ericatious soil or what sort of soil do they prefer

Will you be growing your plant in a pot, or in a garden border? If in a pot, they don't need special compost - multipurpose is fine, but add some grit or Vermiculite for good drainage.

I did a quick internet search for Oleanders and found lots of information, including this: https://www.rhs.org.uk/advice/profile?pid=810

Hi, welcome to GoY, you don't say where in the world you are, but as you're asking about Oleander, and there is only 1 species that's hardy, I'll assume you live somewhere that is warm enough to grow them outside, where they like a moist, but well drained soil, in full sun, they're not too particular about the ph, as long as the soil isn't too acid, if on the other hand you're in a colder part of the world, you would need to grow them in a cool greenhouse, in a loam based compost such as john innes number 3, with some added grit, Derek.