Viasat modem RG1100 won’t connect Orbi CBR40

> I have an Orbi CBR40 router and it has trouble with Viasat Modem
> RG1100. [...]

   "trouble" is not a useful problem description.  It does not say what
you did.  It does not say what happened when you did it.  As usual,
showing actual actions (commands) with their actual results (error
messages, LED indicators, ...) can be more helpful than vague
descriptions or interpretations.

   In this case, you're far enough off course that a good problem
description might not be needed.

> [...] Is there a better Netgear router I should be using?

   Almost any?  A Netgear mode "Cxxxx" is a cable-TV modem+router, which
is approximately useless with a ViaSat gateway.

   Why do you want to use the CBR40 with the RG1100?  Is there a problem
with the RG1100?

   If all you want from the CBR40 is extended wireless-network coverage,
then you might be able to configure the CBR40 as a wireless access
point.  See for example:

      https://community.netgear.com/t5/x/x/m-p/1463500

That's written for a Netgear C6300-as-WAP, but the steps are about the
same for any other router (any make/model) which lacks a one-step WAP
option.  (Especially similar for another Netgear Cxxxx.)