Try looking at this its a good start: SQL Server Online.

Also visit Microsoft they have a windows server set up limited if you are trying to learn but if you plan to use for business that can get expensive to purchase a license.  As a crewman I say take the classes from beginner and work through them you may be asking for something you may not understand.

If you only have 1 or 2 users that need to be remote, it may be more cost effective to setup a remote connection using some 3rd party software like remotepc, teamviewer, etc. Into a local machine/terminal inside the network. Everyone would need their own connection, it can also be done with a multi-user license server. Just another idea. You can see other options here Access Online

I cover setting your database up on a local area network in Access Expert 21. If you already have a LAN based setup, and you want to allow one or two users to connect to that remotely, then you can set up PCs for remote connections using Chrome Remote Desktop. This is what I use when I travel. Otherwise, if you want your whole database to be "in the cloud" then use Access Database Cloud.

Against Richard's preference, I have actually setup a working small office (1 person, myself) with an old school batch file, linked to Windows Startup to get my One Drive account seen as a "local drive" on each of 3 computer setups (2 at home, 1 as my remote setup on an Asus Tablet).

With this method, I can properly set a base folder for my external sources via my OneDrive for Business account on the backend, and run the frontend successfully on each system. Before, I was having to relink on each computer, not good.

Through a web search, I came across the method on Tech Republic, with screenshots.

1. Create a new text file and name as [yourfile].bat.
2. Edit said file and with 1 line of code: subst [drive letter]: "folder path"
3. from the run menu --> Open Windows Startup: shell:startup
4. Create a shortcut --> locate the file, and name it as you wish.
5. Reboot to see permanent results

Brian, that will work... until your database corrupts. Trust me. OneDrive and other systems like that were not designed for how Access handles file I/O. But don't listen to me... enjoy having to compact & repair daily and restore from backups. :)

I've got a whole video on this and why you shouldn't do it coming up soon. In the mean time, I will refer you to my Access Online page.

See: File Sharing

Let me clarify, as I said in my video, if you are the ONLY USER working on your database and you only have it open on ONE DEVICE, then sure, you can use a file sharing service. However, don't open it simultaneously on multiple devices and make sure you give your whole "network" of devices sufficient time to sync the file or else you will lose data.

Richard, yes, I **AM** the only user on my 3 split backend DBs at 2 MB and under, and I wouldn't have attempted that method above, which is strongly NOT SUGGESTED for 2+ users. It still works for myself in the current learning curve moving from Google Docs, which became too limited for my needs, including the ability to __properly__ share reports to my accountant in Excel from Google Sheets.

I do have other options, and am finally looking into them. The Access Database Cloud from here, as well as my web host, Interserver.

As for sufficient time for syncing, I do give them that, monitoring the timestamp on my Windows Tablet before I open up a Workbook, edited and saved on my phone, that is connected to 1 of the DBs, with 3 tables at 2 fields max ea. I can only properly update the Queried connections in the Workbook on a desktop, laptop, or tablet in Windows, so even then I've learned to give them ample time. On my Android phone, I just have to guess at the time, and wait for "reload".