Talk to me about inverters

Thank you for the answers. It would be use mostly for,microwave,coffee maker ,iPad,phone charging

First forget Charge while driving that is not the inverter's job. The Tow Vehicle (Trailer) or Main engine (Motor home) alternator handles that via an isolator solenoid or device... As for the rest

You want a good 3-Stage Plus charger section. Programmable is best in case you change battery types. but not absolutely needed You also want one where you can set the max amprage to around 30 percent of your battery bank's C/20 amp hour rating (IE 440 amp hours (2 six volt pairs) 130 amps) or less (100 is fine)

And a True sine wave inverter TSW or PSW (another name for 'em) are nice clean Sine Wave devices everything works like it is supposed to no exceptions provided the inverter is big enough.

Finally you need to decide what "Big enough" means. And also your battery bank
1 pair of GC-2 Golf car batteries (200-220 amp hour) per Kilowatt of Inverter is MINIMUM recommended.

Just electronics (TV/Radio/Computer/Sat receivers.) 1000 watts or less. 500 may well do it.
Add the microwave kick it up to 2000 watts.

I do not recommend adding beyond that save for fans and the like but if you want to add air conditoners
1; You need a Diesel to carry that much battery
2: 30000 watts or more

Inverter / charger setups will charge your batteries while plugged in and become an inverter when you are not connected to shore power. If you want to charge your batteries while driving, that is handled by the engine alternator.
More details about your RV would be extremely helpful.

What do you mean the old one did everything? We don't know anything about your setup because you have no profile. 1750 amp makes no sense.

stand alone inverters do NOT charge batteries

combo inverter/charger ... will charge batteries when 110vac is available
either from shore power or generator power, they use battery power AKA discharge batteries when there is no 110vac available, they make the 110vac from the 12vdc

they do not charge from alternator while driving
that is a separate function of your chassis/engine electrical

are you thinking of TV and laptop and cellphone chargers ? 300w
or coffee maker and microwave 1200w to 2000w

I don't know much about them .old one was 1750 amp? Just thinking, that needing to replace it ,should I just go bigger. The old one did everything I need i guess.

What are your requirements? How much power do you need and how often do you need it.
We need a lot more details.