Good luck, welcome to webdiplomacy. Perseverance is a virtue in the Diplomacy caper. Double and triple check your orders to avoid mistakes. Others have made excellent suggestions.
Here's a tip .. if you see an experienced player with heaps of points click on their player name & go to their home page. Then look at their completed games... Look for games where they had solo wins..find an interesting game and open it up.
In the bottom left corner is the Archives function. Select Maps.
This will bring up the maps for Spring and autumn moves for the whole game.. scroll down through them to the spring 01 map.. and then work slowly up through the maps..
Takes a bit of getting used to deciphering because retreats and builds are also shown..
You can discover interesting tricks, learn important lessons.
For example, I thought I knew how to play England well and was aware of the need to build as many armies as possible and not over indulge in building fleets.. building too many fleets and not enough armies is an easy mistake to make.. then I was looking at a top 2% players previous games and went through one of his solo wins with England.. his game really showed me what was possible in how few fleets were really needed.
Or you can use it to find out a probable opening strategy with particular nations a player might use.. eg, you have Austria, what's the most common opening moves used player with Italy, or the player with Russia when they have those nations?'

Just joined I'll go with that game^^

This game looks good: https://webdiplomacy.net/board.php?gameID=305154

You may also create a new game and advertise it in the "New Games" section of this forum.
Or, you may create a bot game, ie a game in which you will be the only human, and will play against the AI bots. That may be very useful for developing your tactical and strategic skills - not your diplomatic prowess since the bots don't talk. But beware, bots can be hard to defeat

Look for low-bet games, 5 or 10 points, those usually have players with less experience. You can also look at the profiles of people who already joined the game and see how many games they have played.

I am sorry if I can find this information somewhere else on this forum, I just made this account. I'm wanting to learn to play Diplomacy, because I'm going to play with friends on another website.

I have skimmed through some guides and know how the game works. How can I find a game that has not very experienced players? I don't want to ruin the fun for others, since I will play less than optimal. Also I don't want to get beaten hard, because I entered the wrong game.

Any tips? Thanks in advance :)