I don't know of any websites or posts here that I could point you to (I lost everything in a hard drive crash a few weeks ago so my links are gone) but I can give you some basics.
Mountains can go anywhere you want them. The Andes run very close to the coast so that isn't a problem. Mountains are based on tectonics; plates coming together like the Asian and Indian plates form the Himalayas or spreading apart like the North American and European forming the Mid-Atlantic Ridge making Iceland. Some things to avoid: don't put them smack dab in the middle of a landmass (looks static and boring), don't run them like a fence or a wall to separate climates or countries, avoid geometric shapes like circles or squares or letters like a C. Some things to do: put foothills around them, make some tall and some short, run them in subtle curves.
Rivers start in the mountains and flow to the sea via a course of least resistance (ie soft dirt as opposed to hard rock or a steep slope vs a shallow slope). The analogy I always use is to think of a tree with the tree trunk being the main tributary starting at the coast and all of the little branches up near the mountains. You can use the roots as a delta but don't give every river a delta...it's overkill. Lakes have only one outflow that can be sustained, there may be many right after a flood or something but eventually one course wins out. Some lakes have no outflows because they are below sea level or are in very hot places causing fast evaporation. Rivers can split to go around islands or rocks but they rejoin and don't stay split except in deltas because they hit the sea before rejoining.
Deserts can be found generally around the Tropics of Cancer and Capricorn or in the rain shadow of mountains (the area leeward of the jetstream where the rain "bumps" into the mountain and falls on that side leaving the other side dry).
Swamps, fens, etc can be found where there is a lot of water to be collected, thus they are on the opposite sides of mountains from deserts. There are cold swamps called bogs/fens/moors so wetlands can be anywhere except next to deserts.
Don't use too many forests, try to keep a balance with the flatlands.
Other than that you would need a book or class to get more into it. There are many here who could go into those details but it would take a while.
Geo-political things come next like towns and borders. Towns often start at river junctions or river mouths. Once trade routes come into being towns start where roads meet. Some towns start because they are a good campsite after a full days ride on horseback (starts as an inn and grows into a village then town etc). Other towns start as a good place for a fort. Roads are not always straight, they run according to fastest travel so going up and down hills is slow compared to going around them at a constant speed. Borders go out as far as the military can enforce them but generally follow rivers or mountains.
Lastly, you need things like a scale of miles and a compass and labels for those towns and rivers.
This is just a super brief explanation so I'm sure I left out a lot.