is it ok to have multiple accounts

But as my friend told he used 3 one for playing quick pairing one for playing team battle and one for playing lobby but still got banned

#4 no lichess does not keep rules like that and in future also never. Lichess is for everyone and everyone is equal. Magnus only created 3 accounts, or Magnus might have asked the mods for permission.
of course, if you create multiple accounts we obviously get banned (check it and if your account is closed, then try to log in, when u click on log in they will tell "your account has been closed by moderators" and down it will be written "your account has been closed because you have created multiple accounts/ chat banned/ violated lichess T&C)

To clarify: Lichess does not condone excessive multi-accounting, but 2 or maybe 3 accounts is ok by them generally. Just stick to playing on one if you are not sure what to do.

Magnus have many acc not only 3 I guess he have 5 but I don't have that feeling my friend told that might be the rule

The TOS says not to create multiple accounts...

Yes it's true I am saying that but I think GMs can make it can be wrong also I don't know

@komokoid no, lichess won't do like that, everyone is equal, whether he is GM or noob they are equal

But I see GMs having 5-6 acc they don't get ban that's why I thought I said I May be wrong

You want many accounts on lichess, well then I hope you enjoy violating the Lichess Terms of Service!

I don't think you should make several accounts.