most of us on this forum are self taught...learned...still learning...as we went along. wish I had a forum like this though when I started cos it would have helped me avoid some expensive mistakes.
Sorting out a garden is not really complicated...if you have time that is the most important requirement
Firstly, can you say something about the garden? its size, the type of soil...does it get boggy in the winter or is it sandy and dry out quickly in the summer?. Next to decide what is already there, what you want to keep, what you cant move.
At some stage before you actually plant things you will need to do a PH test...its a simple thing to do. go to a garden centre and get a PH tester, very cheap, and the instructions will tell you what sort of soil you have as far as growing plants is concerned. This bit is when you have cleared your garden etc.so not something to consider right now
Clearing weeds? What state are the weeds in? are they huge, totally covering the garden? are they perennial weeds....like bramble, etc? Perennial weeds can be sprayed to kill them and then the ground can be dug over. All roots binned to discard, big stones removed. The ground needs to be cleared and clean and levelled. I actually enjoy this process as you can see the great progress you are making.
So, the size of the garden and the state it is in please Eri, and then concentrate on clearing it out. Once your garden is clean you can decide what you want to use it for, a lawn at all? plants etc and a place to sit?
When it comes to the design ask us again. you will get loads of conflicting advice but mine will be the best.....ha ha