I think the best way to make your conversations more comfortable is to make plans with topic for each conversation. Also if you have limited vocabulary you can write for each topic some relevant words and frases. Here are some ideas of topics:
- sport (what team support, what kind of sport is goin to, championships and etc.)
- pets (what pets do you have or wanted to have, what was your first pet, funny situations with pets, how to choose name for pet ...)
- traditions (family traditions, national traditinals, traditionals with your friends and so on)
- holidays (national holidays, how is your family celerate some holidays...)
- literature/cinema (favorite books, films, actors, writers, TV series...)
- traveling (what places you have trevel to or dream to travel, interesting places in your country/city, what kind pf traveling do you like, your best vacations
- dreams (what will you do if you win will lottery, what are you dreaming to do but you have lack of courage, what superpower would you choose)
There are many more topics. The main thing is to hear your interlocutor, ask questions about his stories and topics.
Good luck! :)
We use site TED.com for choosing topic with one of my speaking partners. For example, I chose an issue and send him the link to approve it. Next time he does the same.