In my opinion.
#1. Every time is good to build a crypto portfolio, there is no way to predict the market when to make a better shot to invest in crypto. But if bitcoin was made in a double amount in dollar value compared to last year, it will have the potential to double again the price in the future. Look around, bitcoin adoption was quickly spreading and for sure this has an effect on the price since it is a fixed amount in total in the market cap. So investing in the long term has a guarantee to make you a profit if you want to start your portfolio now and a friendly reminder, be careful with altcoins investment, it is better on bitcoin because it feels safe.
#2. No one knows if there is a bear market, so far there is no bear market. But as I said above, no one knows.
Adoption was going on and I think more and more countries that crypto becomes legal tender, so it is impossible to have a bear market again. As I said, look around.
Now that crypto is gaining more investors day by day and crypto adoption is increasing massively I don't think that the next bear market will be crazily low like 2018/2019, what do you think?
If you believe and are willing to take a risk, just invest it of what you can afford, and welcome to the crypto world.