In the early stage of a tournament, we are just trying to accumulate chips, and outlasting other players do not yet have significant value. So the best strategy early in a tournament is to play the same way, you would play in a cash game. The main difference is, most tournaments play with an ante, and most cash games do not.
If there is an ante, we need to play more hands (looser), because there is more chips to content for, at it cost us to much, if we constantly sit there and fold while still paying not only the blinds but also the ante. The other difference to a cash game is, that except for the first few blind levels, stacks will tend to get shorter like maybe 40-60BB rather than 100-200BB. This widen our stack-off range and change the value of different hand types.
As for aggression this term is often a bit misunderstood. The aggression factor is the ratio between bet and raises to calls. If this factor is two, we are betting or raising twice as often, as we are calling. This is considered a neutral number, because when facing a bet we should sometimes fold. So if we and our opponents bet or raise at the same frequency, and we fold half the time, we end up with an aggression factor of 2. However folding is not passive but neutral. So we can also have a high aggression factor or aggressive playing style by rarely calling.
So is it possible to be to aggressive then? Absolutely yes. If we only continue, when our hand is strong enough to raise, thats definitely not optimal. We do want to have calling as one of our tools, we just dont want to call to much. Like regularly calling all the way down with bottom pair, as we see fish do. However most likely OP is considering, weather he bet or raise to much. And this could certainly also be possible.
If there are many multiway pots, we do not want to try to win all of those by relentlessly betting into several people with air. If we missed the board, chances are, someone else hit it and will not fold. So in these situations it will generally be better to take neutral actions by checking and folding. We can also be to aggressive by betting for value with a hand, that is to in between to get called by worse.
Like maybe betting flop, turn and river with second pair. Here we should also take a neutral action by checking at least one street to not value own ourselfes, but unlike the other situation our goal is to get to showdown. So maybe we bet flop (aggressive), check back turn (neutral) and then call a bet on the river (passive) and win at showdown against a busted draw.