Take a look at the UKBA webpage here called - English language requirement
You'll see there's quite a selection of different tests available, different providers and different test centres.
The UKBA site states that:-
"In the test, you will need to demonstrate a basic command of English (speaking and listening) at level A1 of the Common European Framework of Reference.
Someone assessed at level A1 can understand and use simple, everyday expressions and very basic phrases.
You will not need to demonstrate reading, writing or grammar skills.
Plenty of forum members have taken a TOEIC test which is done by Hopkins.
Many members have also taken IELTS
Do be aware that IELTS is a slightly higher level (B1) so if you're not confident with your English that might be quite a stretch.
Many of the test centres can accommodate review classes for those whose self-confidence needs a boost.
Once you've reviewed the UKBA information don't be shy to ask any specific questions here.
If you're just starting out on the visa journey why not take some time as a very first step to review this thread and follow all the included links to the UKBA site.
All New Guide - How to apply for a Fiance Visa
Read this and again follow the links - Applying for a UK visa in the Philippines
The UKBA advises all applicants to read their application Guidance Notes together with their Supporting Documents Guidance
You can search here in the forum for any areas/topic of concern or you can ask as many questions as you need right here in your thread.
Please be sure to fully understand all requirements.
Plenty of folks here to support and explain immigration rules
Good luck
Hope this helps.
Don't forget there's a requirement for TB Screening before visa application.
Here's the needed detail - Tuberculosis testing in the Philippines