Yes, now is a perfect time to start buying. Both of them are good, normally I would have said Bitcoin is a better choice at all times, which it is indeed. But Ethereum transfer to PoS soon might lead to a boost in the price.

We are getting close to the launch of the ETH 2.0 version of Ethereum which would be a better version that would rely on proof of stake, and when it happens (even before it happens) we would start seeing the price going up. Ethereum has also been performing quite well as of recent, today was over 2%>. If you choose to invest in Bitcoin, it is still a good choice, normally you would he told to invest in BTC, or you can diversify for both.