I have the free version and did everything to put the textures but I do not see anything, only the default particle
I just want to know if you have to download the textures or is it a mistake or not coming at me to download version
No, you need to provide your own textures!
For starters, you can look in the Standard Assets packages which ship with Unity. Go to the ‘Assets’ menu, and look in ‘Import Package’. There should be a list of useful things for you to start off with.
However, these textures and assets are only very limited in what they can be used for- if you want to go beyond that, you will need to source your own textures, models and sounds. Thankfully, Unity is extremely forgiving with format requirements- it can import almost everything you could want, and treats them all equally in the editor. I think it’s that feature, more than anything else, that sets Unity apart from other commercial game engines out there.