BTC made correction so , is it right time to buy altcoin

That will be up to you because we have different analysis, which will happen to the other people.
But for me, I think it is the right time to buy the top 10 altcoin list and hold it for a while.
If you want to buy the altcoin, you need to analyze to find which coin will be potential for you. Your potential altcoin will not be the same as other people, so you need to find it yourself.
Maybe it is not easy to find one or more altcoins, but I think that will be worth it for you as we know that the altcoin season will come soon.
While the bitcoin price is still at the correction, you can find the potential coin by analyzing every coin you think will increase later.
But you need to be careful and don't follow other people's suggestions to find the coin before you analyze the coin.