Problem with WiFi connection -Android tells me it is not secured I didn't find a anwser to my question yet on the forum, but as I am new, I may just have overlooked it.

I had a trip to Warsaw today and had troubles connecting to WiFi. I would select the wifi network (either at the airport airport, or at my working place in Warsaw where I have a business trip) and then I would select the option "connect to ". This is usually where I need to put the login and the password. But this time, for these networks, he gives me a sign with a barred lock (I guess it means it is not secured?)
On my laptop he also tells me that it is not secured but he still gives me the option to go ahead anyways, which Android does not. I trust the network (it is the wifi network of the Polish academy of sciences...) and I would love to be able to do the connection whatever Android thinks of it.
What should I do?
I don't know if this helps, but my phone is a wiko rainbow 4G.
This happens with me too, whenever I try to connect to my  Wi-Fi when there is some maintenance job going on by my ISP or when the router lights are on but my final connection has not taken place ( I don't know why but it connects only after 5 minutes after all router lights are on ).
So I would suggest that you need not worry any of the above problems might be there.