Unlike traditional business phone systems offered by big telecom companies, your LinkedPhone business number works with any desk phone, home phone, laptop, and even your personal cell phone.
Last, make sure you keep this voicemail account up to date, especially if you have some kind of "out of office" message, telling people where you are. Michael Hyatt updates his voicemail message every day-- it may seem excessive, but it lets his callers know that he regularly checks his voicemail, cares about messages he receives, and is likely to get back to them.

In practice, most businesses are simply handling this on a case-by-case basis since COVID is a temporary problem. Most home networks can handle the extra load as long as the employee makes sure that other latency-sensitive traffic, like gaming or video streaming, is kept to a minimum during the hours when they need to talk. If some home routers develop problems, IT staff simply build a queue and handle those one at a time. Sometimes they'll be able to access the router remotely with the employee's permission, sometimes they'll have to walk that employee through configuration steps to fix the problem. Sometimes the employee will just have to live with it unless the company springs for a new router or a higher bandwidth tier from the employee's ISP.
A relatively unprofessional one — like mine, for instance — does the opposite: It encourages prospects, recruiters, and potential connections to run in the other direction.