Yeah, its better to start with smaller projects at start
Yes you can make mechs, in fact not so long ago a user on the Polish section of the forum made an announcement of his game with mechs, you can check it here, but its in polish - <!-- l --><a class="postlink-local" href="http://www.esenthel.com/forum/viewtopic.php?f=21&t=1648">viewtopic.php?f=21&t=1648</a><!-- l --> (on the top you have some screens)
and here im copying links to more screens
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paste your screens here on the forum when youll have some demo too!