No "texture" option?

Hello! I'm trying to start working on a game again.. I've inserted custom textures prior but now whenever I attempt to there's no option for me to be able to upload the texture? The light mode one is mine, I couldn't find anything on google and would love some help! I have a feeling I'm just very blind or something lol

https://preview.redd.it/szot9v73pcng1.png?width=263&format=png&auto=webp&s=4f5acd8d77371ee39360717ee6a5dabf981f04c1

https://preview.redd.it/n0lixgz3pcng1.png?width=278&format=png&auto=webp&s=0abe7d4ef4c908c6a5f3504ba9df88716c835754