Which Ending of Undertale I got? and What remaining endings I have now?

Solution 1:

Since you say I killed Toriel, you certainly got the Neutral Route Ending, as Toriel is one of the monsters you must spare in order to obtain the True Pacifist Route Ending.

In order to obtain the True Pacifist Route Ending, you will need to restart your game from the beginning and kill no monsters at all while also befriending Papyrus and Undyne (so, go on Papyrus's date with him, pour a cup of water on Undyne when given the chance, and later go to Undyne's house when invited to do so by Papyrus). If you do all this correctly, after defeating Asgore and Flowey a second time, you will instead get a different conversation with Flowey that will direct you to a newly-unlocked sidequest and bonus dungeon that will lead you to obtaining True Pacifist.

Additionally, resetting or deleting saves is fine in your situation; the cloud save resync effect in Undertale only changes your options if you have obtained the Genocide Route Ending by murdering every single possible monster, which you have not done.