Hi MindaugasSeo , welcome to Galactic Talk!

I want to do something similar like - deposit 0,01 bitcoin, then to convert 0,01 BTC to 6,46Usd and then to convert to 5,85 Eur and then to send these 5,85 Eur funds to my PayPal account or vice versa. This is not possible with Stellar right now or is it? Why? Will it be possible someday? When?

The stellar network is a perfect fit for this use case. In theory you would use a BTC anchor to deposit your BTC on the stellar network. And then you would use the distributed exchange that is part of the Stellar network to convert between different currencies. And in the end you would transfer the Euros to your PayPal account through a PayPal anchor.

The reason why it doesn't work right now is that there are no anchors accepting BTC or PayPal. As the Stellar network grows and more financial institutions join it, this should be an easy and fluid task to do.

Yes, I am interested to invest in Lumens, but I am afraid that the market will be flooded with new Lumens (multiple give away programs) and the price could slide a lot, so it is more like donation rather than investing right now, isn't it?

For me the price of cryptocurrencies always looks a bit random and that's why I don't like to "invest" in them. If I remember correctly Stellar.org was once also accepting donations. I'm not sure if they will do this again, but if they do it's a much better way to donate to the organisation than buying Lumens. On most exchanges you will not be buying Lumens directly from Stellar.org, it will be from other traders. Having a bit of stake in Lumens makes it more exciting to follow how the technology unfolds, as the price is positively reacting to good news. But following Stellar development can also be a rewarding experience without owning any Lumens.