A2 Hosting has SSH access
Whilst I am here, I want to enlighten you and other thread viewers about VPS hosting as it is more suitable for what you want to do which is testing Flarum. It can also save you a LOT of money.
The issue with shared hosting is that it's very expensive for what it offers. At a quick glance, it looks very appealing with all the features that they provide. However, they can also severely limit your access such with things like SSH.
Take siteground for example, their go geek plan is £9.50 / month. This only applies when you buy the yearly package which means you will be spending minimum £120 + upfront. This is not perfect if you want to test Flarum. If you decide to pay monthly, then its £9.50 for the first bill and then £20 every month after that. This is an issue with other shared hosting providers as well.
VPS hosting will tend to your needs better.
VPS hosting is like renting. You are given a dedicated space that you can do whatever you want in contrast to living with room mates (shared hosting).
With VPS hosting you have complete access over your server hence you can use SSH etc.
The biggest advantage is cost. Its billed hourly meaning if you decide that you don't want to run a forum after a couple of days, you only pay for those hours and not for the entire month or even year.
Cloudways is surprisingly affordable, and popular VPS solution that has SSH access.
It comes with 3 day trial period where you can host a fully functional Flarum website without giving your payment details.Its cheapest plan at $10 a month or $0.0139 /hour should you want to continue testing longer.
If you want even cheaper hosting with the same specs, you can try Digital Ocean/Linode/Vultr. Its the unmanaged version of Cloudways hence it's much cheaper whilst offering the same specs. This can be tricky for Linux beginner but there are services such as Runcloud and Server Pilot which give you a control panel to manage your server.
You can also use Free Flarum to have a play around with.
In conclusion, you have many pathways available to test this brilliant software with. However, with this post, I wanted to save you money by giving you viable alternatives.