Before dedicating your computer's resources to help Ukraine in the cyber war ageist Russia, it's important you cover your identity as some Internet service providers will not like you doing this and may pass your information on in a report of cyber security violations.
a lot of ISP's won’t mind as you're helping Ukraine, for example Virgin Media in the UK.  _________________________________________________________________

    Follow this guide to keep yourself secure.

Get yourself a good VPN service.
A VPN hides your public IP address by substituting it for the public
IP address of the VPN termination host or its internet breakout. So in case of an investigation your
public IP will not show.
Here’s a list of VPN providers. Some of them are paid and others come with
a free trial:
https://www.top10vpn.com/top10/freetrials/?v=header&bsid=c15ense1kw287&gclid=EAIaIQobChMIs8i9ouii9gIVnIODBx07PgGMEAAYAi
AAEgJkkfD_BwE

Use a web Proxy or Browser addon to protect your activity’s when using a
pre-ready automated HTTP flood site.
A Proxy is a quick and easy way to hides your public IP address from websites you visit.
there are several ways to run through a proxy, the most common being a simple web proxy, this is a website that allows you to redirect all your activity’s through there server's, they are commonly used in schools or places off businesses to access blocked sites like YouTube, Facebook ect..
Heres a list of proxy websites found from a quick google search..

You can find a Browser Addon for proxies on your browsers Web Store, e.g., Chrome Web Store.
ensure the addon you choose is verified by google or whoever provides your browser, some proxy plugin developers sneak malware into them.

The Tor browser is a free, open-source project enabling you to surf the web anonymously. The title is an acronym originating from the phrase “the onion router”.
The Tor browser network is built of layers upon layers of independent nodes run by Tor users.

The key difference between Tor and a VPN is how there are multiple VPN tools and service providers available but only one Tor browser network.  

Tor relies on a decentralized layer of independent nodes to transfer data securely, while VPN software connects to a central server to provide a secure VPN tunnel.

Another common difference between the two is the specifics of their use.   

If your online activity is related to the transmission of extremely sensitive information or might get you in trouble in countries with strict censorship laws, Tor is the best option to go for. The reason is obvious, since VPN providers still have to be registered, pay taxes, and comply with legislation

When should you use Tor?
Tor is more effective than a VPN in the following cases:

You want to stay safe while accessing geo-restricted content.
Using Tor is a good way to protect your privacy when you’re trying to access content that’s prohibited in your country. This includes geographical limitations (accessing US-only content from Europe or Australia for example), avoiding censorship in countries like Iran and China, and much more.

You want to access the dark web.
Tor’s Hidden Services is also the gateway to the dark web. It is made up of websites that are only accessible through a Tor connection and cannot be found through search engines like Google. The dark web is often associated with criminals whichis why it's illegal in some countries.
You want to stay away from browser trackers. If you want to use the internet and leave no digital footprint, using the Tor browser is the best solution. It’s almost impossible to trace a connection to the original user, so you can surf the web without leaving any identifying signs behind.