the doses for lyme for all drugs are typically the maximum dose used for that antibiotic in adults for other serious infections see for example
https://www.drugs.com/dosage/azithromycin.htmlwhen combinations are used each drug in a combination is typically used at this dose.
but each may be started at lower doses to establish tolerability
these are all relatively safe drugs - but everyone is different, lyme and co may weaken the function of organs and multiple drug combinations increases the risk of liver, blood count or sometimes kidney issues - so safety labs should be performed each few weeks
the other approach to consider is pulsing - for example - Dr J favours this for all his patients
pulsing reduces the risks of taking multiple antibiotics.
in this case a greater number of different types of antibiotics are typically used
but they are not used continuously
Dr J has videos and lectures available on YouTube if you want to get a feel for the concepts and approaches used