Hiya
Once you have been through the cycling process, which can take a couple of weeks or so, be aware that with small tanks (one of my tanks is a 60L, which I consider small) water quality can change quicker than in larger tanks, so small frequent water changes are a good idea.
And with a 34L tank even when fully stocked with fish you won't have heaps of fish in there, be careful of overcrowding, so choose your fish wisely.
Good luck with your tank, fish are such cool pets but do require more work than you initally think, all the best and just keep trying there is always more to learn with fishkeeping, I've had tanks for 4-5 years and I am still learning.
:lol: