Upgrade RAM from 64 to 128mbi ?

Mikrotik RB941-2ND-TC + memory full+32mbi?
I buy this router one week ago and I’m new with
Mikrotic router!
Can I increased it the memory to 64 or 124mbi?what brand is comparable to mikrotic router?
Wifi antenna to slow signal! ? How to increased it?
Soldering antenna on board?
Thanks from Spain and love.

You are talking about HAP Lite TC. This router board is built with 32MB RAM and it is not possible to upgrade the RAM in this type of RouterBOARD.

You have bought the about cheapest MikroTik router/ap (except the hAP mini).
It is basically just a toy. You could maybe use it as an extra router in a remote room to have some extra coverage there, and connect some wired equipment as well.
To do any things for which you would require more memory, you should really buy a more expensive model which has more memory and more capabilities.