Ah! You're in the Philippines. Half your country is 120/240 split phase like North America, and the rest is Euro style 230. This results in some odd "idioms" and you're looking at one. But a very good one -- Europe and the rest of Asia should do this!
Nobody puts fuses on neutrals, not even UK. This is to save money, the logic is a neutral can't carry more current than its partner hot. That only works if they're monogamous. A wiring mistake can overload a neutral, and then your house burns down.
The Philippine hybrid
This is a common USA-style 240V panel. It is meant to have two "hot" rails each 120V from neutral (missing here). Most circuits would use a 1-space breaker which clips onto one lug, and neutral would not be fused. 240V breakers are double-width, both hots are fused, and neutral (if used) is not fused.
Here you have a unique-to-Philippines hybrid: a USA-style panel where the two "hot" buses are being used as hot and neutral. That is great. It means neutral is fused. Less great is that every circuit takes a 2-pole breaker, so you run out of space really fast. In the USA this is a 14-space panel; for you only seven - alarmingly small. Get a much bigger panel if there's any conceivable way to do so.
Backfeeding the panel
Why did I say 14/7 when there are obviously 16/8? Because this panel has no main breaker - but what's more, it has no lugs. The only way to feed power into this panel is fit a "main breaker" (typically in the upper left) in 2 spaces as if it were a normal breaker -- and backfeed it. This means power flows backwards from the wires, through the breaker, to light up the panel. There's no choice, a main breaker is the only way to energize this panel.
It's fine to backfeed normal breakers. You cannot backfeed a GFCI/RCD breaker.
Then, all the other breakers fit and work in the normal fashion.
