Boiler pressure

You’ll be absolutely fine, it may be that your incoming mains pressure isn’t very high, I’ve had systems that just fill above 1 bar due to the mains pressure. If you’re having to re pressurise your system regularly then you could have a leak somewhere, but usually a 1 bar leak is fairly obvious unless it’s beneath a solid floor or a cracked heat exchanger

No

If the pressure gauge doesn’t move when you fill the system up, then we can’t determine how much water is in the system, we could have a blocked pressure gauge which isn’t letting us know we either have too much water or too little, this could be potentially dangerous so get an engineer out asap, if your waiting on someone then try ringing around for another engineer if all else fails ring the manufacturer of your appliance and they will advise

No its absolutely fine to run your boiler on 1 bar and on some models of Worcester bosch they have internal filling loops to pressure the system and can look as though there not filling but leave it fully open and it should fill slowly and the needle will rise !!!

To work efficiently the Worcester boiler needs to operate on a standard pressure, between 1/ 2 bar, 1.5 bar is also a good pressure level. It is more than likely that you have a leak or the expansion vessel needs re charging or replacing , your mains pressure coming in to the property might only be 1 bar so that's all the pressure you can put into the heating system