Questions about switching components on a budget bike

Hi,

I have a Btwin Triban 500 road bike, still currently in the Decathlon catalog..

https://www.decathlon.it/bici-da-corsa-triban-500-nera-id_8379069.html

It has MicroSHIFT gears/transmission and a Shimano Tourney triple chainwheel (in fact, the specs and pictures at the Dectahlon website link show it to be a Prowheel Ounce chainwheel but seems by now they have ran out of stock of those and moved to using a Shimano Tourney in it’s place without mention).

Anyhow, I do not much like the Tourney. I don’t know if it is heavier than the Prowheel but it sure looks like it being more bulky as oppossed to skeletal.

I want to replace it with a more sightly, hopefully slightly better quality one and being a complete novice, I would like to know what my limitations are in doing this.

Would it be possible to put a double chainwheel? or would that be problematic because of the particular Microshift gears system on this bike?
I’m prepared to put a new triple one if it’s my only option (in that event, will any Triple do? or do I still have to keep note of any particular specs when buying?).

Double would be lighter and since I never find myself using the 3rd rung down, I don’t see the point unless it’s a must because of the gears system.
Because this bike is not so light, it really aches for any possible weight loss regarding components (I already switched the tires to light foldables and put on light pedals and the difference in weight was night and day compared to the bike in stock form).

Many thanks for any advice
Neil