riot id braindead question

so i am level 5 in league and it is the same account as my valorant account. i wanna start playing league but i want a different name in it

would my names be the same in each game? like if i change my riot name it changes for all games right?

is there any way to have seperate names or would i need to use an account which isnt linked to the other

i think your riot tag is the same across all games iirc

does level 5 mean anything at all or would it be worth to just make a new account for league and start at 1