Try to google seamless textures, or watch a tutorial on how to create them.
Also google Free PBR textures and you will find a lot.
And if you want to create or convert some texture to a more cartoonish version or just edit it, and dont have photoshop you can use Photopea, it runs in your browser so you dont need to download.
Level up ur Graphics by press alt + S and go to rendering, set it to lv 21.
and set lighting technology to Future.
and also add more light around textured items, better light with shadows turned on.
because even online texture will not look good if you are not doing that
or why not make ur own