Real Madrid wants to use their money properly. When they sign a player, they expect long-term service from him. They don't waste money for short-term good performance. Bellingham is a young player. Real Madrid will certainly benefit if they sign Bellingham now. And I believe he will become an essential player for Madrid now as he gradually matures.
Real Madrid have recently bought Camavinga and Tchouameni for their midfield positions, and they have Valverde there who is young as well.
I feel that they won't be making big money transfers for midfielders any time soon.
Bellingham is a great player though - and half of the top European clubs will be interested for sure.
The Real Madrid squad already has many talented and young midfielders but Real Madrid always looks at young players who are playing well of course the goal is for the long term and also to be able to replace several other senior midfielders in the future, but it's also true that it won't happen there was a big big transfer made by Real Madrid on the other hand Dortmund also didn't want to sell Jude Bellingham who was on fire, now even though many other top European teams are also hunting for this young player I think Dortmund can keep him.
Except Jude Bellingham's desire could be key to leaving unless he wants to stay focused on Dortmund.