Hello @waingro, welcome to the community!
As @waingro indicates, you do not delegate part of the amount of your wallet but all of it.
On the other hand, if you want to delegate to more than one stake pool (or simply delegate a part of the total ada you have), what you have to do is create another (or several) wallets and from each of these choose a different stake pool .
If you create different wallets, please be responsible and take all the security measures required to permanently save your mnemonics (the words of your recovery phrase). This is vitally important.
In the not too distant future, it is very likely that you will not have to take these troubles to be able to do this, since multi-delegation will be available from a single wallet.
Greetings.