What is the meaning of games that are: open, closed, semi-closed?

Guidance is appreciated.

Closed basically means lots of pawns on the board, hard to navigate easily.

Open means not lots of pawns, easy to navigate. Bishops like these positions.

For those who wanted to know, Horseys like jumping!

anddd destroying my ego by forking my queen and king :(

I think #2 summed it up pretty much. To revise what TheChessPlayer21 said, an open game is a kind of 'loose' or 'free' position where bishops have open diagonals, and there is space on the board. Closed is when the board is filled with pawns blocking the development of the queen and minor pieces. For example the French Defence could be a 'closed' position, because in some variations there is not much space for black's minor pieces to get out and develop. Some people call these situations a "positional squeeze"

If on the other hand you are referring to these terms as openings designations ("open" = 1 e4 e5; "semi-closed" = 1 e4 anything else; "closed" = 1 d4) then I think they're pretty outdated and don't really mean all that much.

@TheChessPlayer21
@Tommy_Chess
@MrPushwood

This is very helpful, thank you.

Semi-closed? I wonder whether you mean semi-open? Openings are traditionally classified in three categories:

1. The open games, everything which starts 1. e4 e5
2. The semi-open games, everything which starts with 1. e4, but is not followed by 1. ...e5.
3. The closed games.

This is traditional, but often highly misleading. However, the terminology is used even in modern works like John Watson's Mastering the Chess Openings series. Talking about misleading, for example the Ruy Lopez Breyer variation can hardly be called a variation that typically leads to open positions.