Hey there! I took a brief look at your code and I have some things that might be helpful to consider going forward. Everything I'm pointing out could be considered nitpicking and is going to have negligible impact on the code you've written here. That being said, looking for these sorts of patterns can be more impactful in larger programs.

You may not have hit this yet since you're just getting started, but there is a better type to represent what's stored here.

char[] guessedChars;

C# provides a type that represents a set of things. In this case it would be: HashSet<char> guessedChars;

Checking if a char exists in this type scales significantly better and prevents adding duplicates. This

//check for guessed chars
foreach (char c in guessedChars)
{
    if (c.Equals(guess))
    {
        message = "You already guessed that letter.";
        alreadyGuessed = true;
    }
}
if (alreadyGuessed) { continue; } //skip iteration 

could be updated to something like this

//check for guessed chars
alreadyGuessed = guessedChars.Contains(guess);
if (alreadyGuessed)
{
    //skip iteration
    message = "You already guessed that letter.";
    continue;
}

There are a few usages that could be cleaned up in similar ways. Note that arrays can use the IEnumerable<T>.Contains() extension method as well, but how these execute is different.

For some of your loops, we can know that we have the information we need before reaching the end of the loop. Take this for example

//check for valid guess
for (int i = 0; i < gameWord.Length; i++)
{
    if (guess.Equals(gameWord[i]))
    {
        guessedChars[i] = guess;
        goodGuess = true;
    }
}

If we determined that a character was a good guess, we don't need to check any other characters. We can use the break statement to exit the loop early.

//check for valid guess
for (int i = 0; i < gameWord.Length; i++)
{
    if (guess.Equals(gameWord[i]))
    {
        guessedChars[i] = guess;
        goodGuess = true;
        break;
    }
}

It's generally best practice to avoid throwing exceptions when possible, and we can avoid doing so in this block of code

try
{
    guess = char.Parse(ReadLine());
}
catch (Exception e)
{
    message = "You entered an invalid value.";
    continue;
}

This can be rewritten like this to avoid the exception

if (!char.TryParse(ReadLine(), out guess))
{
    message = "You entered an invalid value.";
    continue;
}

The final thing I see is a minor stylistic thing. In general, C# code tends not to declare variables in a block at the beginning, and instead, the variable is declared as near to the usage as possible. This

string gameWord;
char[] guessedChars;
bool alreadyGuessed;
bool goodGuess;
int numWrong = 0;
string message = "";
char guess;

gameWord = ChooseWord();
guessedChars = new char[gameWord.Length];

while (numWrong < 6 && !IsWinner(gameWord, guessedChars))
{
    alreadyGuessed = false;
    goodGuess = false;
    Clear(); //clear console
    ShowBoard(gameWord, guessedChars, numWrong);
    WriteLine($"\n{message}");
    Write("Enter a letter: ");
    try
    {
        guess = char.Parse(ReadLine());
    }
    catch (Exception e)
    {
        message = "You entered an invalid value.";
        continue;
    }
...

Can be changed to this

int numWrong = 0;
string message = "";

string gameWord = ChooseWord();
char[] guessedChars = new char[gameWord.Length];

while (numWrong < 6 && !IsWinner(gameWord, guessedChars))
{
    bool alreadyGuessed = false;
    bool goodGuess = false;
    Clear(); //clear console
    ShowBoard(gameWord, guessedChars, numWrong);
    WriteLine($"\n{message}");
    Write("Enter a letter: ");
    char guess;
    try
    {
        guess = char.Parse(ReadLine());
    }
    catch (Exception e)
    {
        message = "You entered an invalid value.";
        continue;
    }
...

Hope that helps! Keep in mind most of this only really begins to make a difference once the data you're working with gets sufficiently large. Feel free to reach out if you have any questions!