None of this is trivially easy though.
A single user can use an Access solution on his own PC.
A system with multiple users requires a different solution. Each user needs access to (ie the ability to use) a database with the relevant forms, queries, and modules to manipulate the data (the front end). All the front ends need to connect to the same set of data, which is termed the back end.
You don't have to "split" a database into two, but for multi-user systems every developer will recommend splitting a database.
So you need two things,
a) a central hosting for the back end, which can be on server located somewhere in the business, or on a remote server, maybe in the "cloud".
Now access doesn't work tremendously fast with remote data, so you would need to test both the connection and performance. The worse your broadband speed, the worse the experience.
b) a local hosting for the local databases. Now if you solved the first problem by having a business server, then the PC's need to be on the same LAN as well. They may work from remote locations, but there will almost certainly be performance issues. If you chose a "cloud" solution, such as azure, as mentioned, then you may be able to work from anywhere, but there may be performance issues.
There may be hosting services where you can connect to your front end database over the internet, but you would need to investigate.
c) Finally note also that although in theory all users can use the same version of the front end, the practice is different, and recommendations here will always be for each user to have a separate copy of the front end. We would not recommend having a single copy of the front end database on a server, used by multiple employees within the company.
A lot of this is going to be "try it and see". You need to be able to build a working database, and then determine the best way (or at least an acceptable way) to use within a working environment.