Three year bronchiectasis sufferer here. BronchX is a chronic disease, but it will not necessarily rule or ruin your life if it is properly treated and if you learn about it so that you can maintain your own health in addition to getting the right directional guidance and monitoring from specialists who work daily with the disease.
Step 1 is to get reference to a pulmonologist with experience of working with BronchX patients. Be polite and friendly with your GP but be firm in your objective to get such advice. As a last resort ask about complaint processes within your GPs practice or look online for the NHS complaint procedure. Alternatively, if you have any savings consider whether they are better spent on paying for some initial analysis and advice from a specialist - it'll cost a few hundred pounds a year and not thousands (although a CT scan might run up into the thousand plus category). One hears apocryphal stories (and it applied to my parents) of older people struggling along with health conditions while keeping money in the bank so they can leave it to their kids. DON'T, your kids won't thank you for your misplaced priorities.
You can expect an experienced pulmonologist to do appropriate scans (if you are paying then let them know if you have budgetary constraints if they think a CT is required - they may be able to flip you back into NHS for that), an extensive set of blood tests including an all-important assessment of the state of your immune system and breathing tests (with and/or without fast walking versions) to establish your baseline FEV's for assessment and future monitoring.
You should expect then a full assessment of your condition, an antibiotic treatment plan - recommending the most appropriate 'immediate rescue' anti-bi to have on-hand for when an exacerbation (Infection) comes on - to be taken as soon as you have given a sputum sample, advice on excercise regimes and self-administered physio and sputum clearance techniques. They might even recommend prophylactic anti-bi regimens if you suffer from overly-frequent exacerbations.
Regular reading of postings by other BronchX sufferers will also give you confidence that you can manage this disease. I highly recommend the bronchiectasis group in the 'Patient' website forums (https://patient.info/forums) which has a large number of sufferers from the UK and other English-speaking countries sharing their advice and experience without the need to trawl through other postings on other lung diseases.
Hope this helps in the long run! Good luck