idk to use toy

i bought a dildo i tried to put it on the wall ( different type of walls ) and it cant stick into my vagina, idk how to sit, i watched a video and that tried to imitate the video but couldn’t i tried different position of dildo on the wall but it doesn’t work for me. the only way it work is if i put it on the floor and ride it.

anyone send some tips how to ride it doggy style