How can i make other Texture for existing blocks?

[late vault]

"own" as in completely new ones?
Then you will need to look into making a mod.

If you just wanna change existing ones then you don't need to download anything special.

[ashen portal]

how can i change the texture of a existing one? can you send me maybe a tutorial video or somthing

How can i make other Texture for existing blocks?

[late vault]

If you only wanna change the texture you just put your texture in
assets/minecraft/textures/block/ and name it the exact same thing it's called in the default pack (so stone.png for a stone block for example)

If you wanna change the model too you'd need to do a bit more

[ashen portal]

ok thank you and can i load the current minecraft blocks texture as with the entitiys

[late vault]

I'm not quiet sure what you are asking
but if you are asking where mob textures go: assets/minecraft/textures/entity/... (exact position in there and the name depends on the entity)

If you need a pack for reference:

!faq default-pack

[torn portal]

Disclaimer: Use these packs as REFERENCE, don't put your models inside them, it just increases your pack needlessly. Also don't put any of the unedited files from it into your own pack. The distributions of default assets in your pack is illegal.

For Java Edition:
(This works the same for all versions, 1.17 is just used as an example here)
Go to .minecraft/versions/1.17 and open the 1.17.jar in there with a zip program. Alternativley you can copy the .jar file and change the file extension to .zip and double click it.
Extract/copy the "assets" folder inside the jar somewhere. It contains all the default models/textures.

For Bedrock Edition:
Go to https://docs.microsoft.com/en-us/minecraft/creator/documents/resourcepack and scroll to "Building the Resource Pack". The download for the vanilla resource pack can be found right above that title.
Alternatively here is the direct download link: https://aka.ms/resourcepacktemplate