Not everyone is cut out to be a Rune Master. That's is OK. You don't have to have extraordinary Runic skill to be a Gothi, however, you should have some basic skills.

There are several different Rune sets. If you aren't personally drawn to one, pick the one that is the best match for your group. The default would be the Elder Futhark, but if your group leans Anglo-Saxon you may want the Anglo-Saxon Futhork. The far Northern groups may prefer the Younger Futhark. Even though you choose to be more familiar with one, you should be a little familiar with all of them.

Once you pick a Rune set, you should learn to write with them. If someone comes up and asks you to write their name in Runes, you should be able to do so. If someone asks you to read what is written in Runes, you should probably be able to do that or at least recognize which other set of Runes it is so you can send them to the right place. Remember that Runes are a phonetic alphabet and don't have a direct one-to-one correlation with many modern letters.

It's probably better if you can learn quite a bit about the Runes, but reading and writing are the absolute minimums to know. It's always best to know more.