There are multiple scams going on where users receive random tokens in their wallet. If you inspect them, you will often see a URL where you could claim some fake rewards. If you try to claim these rewards, you will have to sign a transaction which will then transfer all your tokens out of your wallet.
So best thing you can do with these tokens : send them to an exchange of your choice (like binance). They will credit you the ADA which comes along with every Cardano native tokens and keep the useless and worthless scam tokens.
And no, these tokens wont cause any trouble in your wallet if you simply keep them there.