Remember that if your machine doesn't have an overlocking function that you will have to either learn how to do French seams (to stop fraying) or just be content with using pinking shears to slow the fraying. I don't have an overlocker and have been put off making clothes now because I'm fussy. But I have saved lots of money making basic things that are easily hemmed like curtains and aprons.
As long as the machine has a zig -zag stick you can overlock. I used to just zig zag on the edge of the fabric after it was cut out before sewing together. My machine (a basic Janome) came with a foot just for this, it made it easier to zigzag right in the edge of the fabric.

I learn a lot just by doing, so I probably would not hesitate in getting a very basic pattern, the instructions on the easy sew ones are not too bad to follow. Also the book with the machine should have some good instructions on how to put in zips etc.