Hi @N1loCan ,
Sorry but I do not understand the language of your screenshot.
Forgive me if some of this comes across as patronising but I will need to provide you with some explanation.
A field, or column or attribute type determines how and what acceptable values are stored in it. A String field type will only accept text, Date will only accept date, and a Number column will accept a number value (for example an integer or a decimal). This is a basic concept for any database (Excel, Google Sheets, SharePoint, Access, Dataverse, SQL etc).
You have a Currency field in Dataverse which only accepts a number, and you’re trying to force it to accept both a value (the number) and a string (the currency symbol).
When we create a currency column, Dataverse automatically creates two additional columns.
1. The first column is the currency we already created and holds the value of your currency amount.
2. The second column is a Lookup to the Currency table (a system table). Meaning we then know what currency our value is in. The default name of the Lookup field is "Currency".

3. Lastly, a decimal column called Exchange Rate provides the exchange rate for a selected currency associated with the table with respect to the base currency.

Back to the problem. If you’re using a Model Driven App, you can configure the Currency using the settings I already outlined in my previous reply.
But I what I think you’re trying to do is Patch a number into a Dataverse Currency column, and then display that number in a currency format in your Canvas App, e.g. onto a Label.
Firstly, use the basic example below to Patch a Number value into the currency column:
Patch(
'Your Data',
LookUp(
'Your Data',
'Your Unique ID'= "Some ID"
),
{
'Your Currency Column': Value(Text("10"))
}
)
Next, suppose you have a Label and you want to display the saved value together with the Currency Symbol. Because a Currency Lookup column is automatically added to our Dataverse table (and therefore our Table is now related to the Currency table), we can return Currency Symbol and concatenate it with our Currency Value:
ThisItem.Currency.'Currency Symbol' & Text(ThisItem.'Your Currency Column',"#,##0.00")
I hope this helps.
------------------------------------------------------------------------------------------------------------------------------
If I have answered your question, please mark your post as Solved. Remember, you can accept more than one post as a solution
If you like my response, please give it a Thumbs Up.