Contact your former employer to see if a direct rollover to an IRA is allowed. Most plans do allow this. If so, contact Fidelity or Vanguard or T. Rowe Price to handle the rollover and make suggestions as to how to invest it. If you do not do a direct rollover, you could be liable for taxes on ALL the money, so let the pros handle this! ( I don’t see the point of making it a Roth IRA, and paying the taxes now.) Just do a traditional IRA rollover and keep it growing tax-deferred until you reach the RMD age of 70-1/2. You’re going to be glad you have this money working for you!