I own a Ender 3, I got it 6 months ago and i like to use PLA instead of ABS because it is easier to use in my opinion. I am currently using Ultimaker Cura software and its a good slicer which is free. what type of tools i like to use are Primer, Sand paper, filler, Black wash, masking tape, and paint/ spray paint. These are most important tool to make your 3D object smooth and look good. Sand paper is really good at getting rid of mistakes in your 3D object, but filler is used to fill up holes in your 3D object but you only have a limited time to put it on so you need to be quick. Paint/ spray paint i think its better to use spray paint because its faster and more efficient and paint is slower and you can make many mistakes with it. after you have sanded your print you will need to use primer, it will help make paint stick to you object better. black wash is soapy water with a bit of black paint mixed into it, you can make your project look old and use but it can get a bit messy.
if you want you can watch this video which helped me.
Here are the projects i have finished using these tools